"Siamese Twins"

PBS Airdate: April 22, 1997

ANNOUNCER: Tonight on NOVA, Dao and Duan celebrate their birthday just like other little girls, but they face an uncertain future. They are Siamese twins, so closely joined that doctors aren't sure if they can separate them safely. NOVA follows a family's decisions that determine how or if Dao and Duan will live. An Emmy award winning story of love and courage, "Siamese Twins."

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STACY KEACH: On April 20th, 1993, a plane from Bangkok, Thailand arrived in Philadelphia carrying two small passengers. Dao and Duan are conjoined twins, born attached at the pelvis. Orphaned since birth, they have been sent to America by an international adoption agency to investigate the chances of separating them. There, to meet them at the airport are Barbara Headley, a nurse, and her husband, David, a doctor. The Headley's have agreed to look after the two little girls while doctors at the Children's Hospital of Philadelphia examine them.

BARBARA HEADLEY: Were they in the same orphanage the whole time until a month ago?

ADOPTION AGENCY OFFICIAL: Right.

BARBARA HEADLEY: They were?

ADOPTION AGENCY OFFICIAL: Mm-hm.

BARBARA HEADLEY: Were they happy there, do you think?

ADOPTION AGENCY OFFICIAL: They quite bonded to the workers there.

BARBARA HEADLEY: So this'll be their third time they've been moved actually.

ADOPTION AGENCY OFFICIAL: Mm-hm. Mm-hm.

BARBARA HEADLEY: Yeah. Do they know that they're coming with me?

ADOPTION AGENCY OFFICIAL: Yes.

BARBARA HEADLEY: OK. And they—you think they understand?

ADOPTION AGENCY OFFICIAL: Yes, we tried to tell them, but they said no.

DR. DAVID HEADLEY: They don't want to.

ADOPTION AGENCY OFFICIAL: They don't want to come. Do you think you should tell them that it's us, so that—so they know it's us.

ADOPTION AGENCY OFFICIAL: What you will call yourself for her, with her? Mom and Dad?

BARBARA HEADLEY: She can call me Mom.

ADOPTION AGENCY OFFICIAL: Mom? Dao, Mom. Say hi. Hi. Dao, say hi to Daddy and say hi to Daddy. Hi.

STACY KEACH: Tired after a twenty-six hour journey, Dao and Duan, two little girls not yet three-years-old, begin a new life in a strange land. Their future is uncertain and full of risk.

BARBARA HEADLEY: Dao, wait till you check this out. Yeah, see, car. We're going to go in a car.

STACY KEACH: Two days later, Dao and Duan have begun to settle in with the Headley's who have two adopted Asian children.

BARBARA HEADLEY: Come on. You can do it. Look how pretty. You're so pretty. You're so pretty. You're going to get tickled. You're so cute. So far, they have done really well. They've—the next morning, they woke up and they felt real comfortable here and they've been smiling and laughing and they learned how to say the word dog and they've just been enjoying themselves a lot. And they feel very comfortable.

STACY KEACH: Thousands of miles from Thailand, Dao, and her twin sister, Duan, are adapting quickly, despite speaking no English. But later today they face a crucial test.

DR. JAMES O'NEILL: How long have you been with the babies?

BARBARA HEADLEY: Two days.

DR. JAMES O'NEILL: Two days. Well, you're very good at it so far. That's OK, that's just fine. It's OK.

STACY KEACH: Dr. James O'Neill, Head of Pediatric Surgery, is one of the world's leading experts on conjoined twins.

DR. JAMES O'NEILL: Now, what I'm doing now is trying to feel the pelvis.

STACY KEACH: Conjoined twins are very rare. The Children's Hospital of Philadelphia, which has carried out eighteen twin separations, more than any other center, only sees one case a year on average.

DR. JAMES O'NEILL: They have a single—a single anus.

STACY KEACH: But if anyone can separate Dao and Duan, it is O'Neill and his team.

DR. JAMES O'NEILL: Conjoined twins rank among the least common disorders that pediatric surgeons encounter. It is believed that the occurrence may be anywhere from one in a million, as a high estimate, to one and a half million. Conjoined twins were supposed to be identical twins whereby a fertilized egg was meant to be completely separated into two sides which would then develop into two separate individuals. Here, the cleavage is not complete, so you do have identical twins, but they're connected instead of being two separate individuals. Depending upon the level at which cleavage is incomplete, you may have junction at the chest, the level of the head, some at the shoulder, the abdomen or the hips. And it's highly variable, and there may be combinations of those forms, and this is why each of these is a very individual circumstance. Now that I've had a chance to see the babies and their condition—

BARBARA HEADLEY: OK.

DR. JAMES O'NEILL: —what I—my next step will be to set up a series of diagnostic studies, and when you'll come in for the, what we call imaging studies, then the babies will be seen by other consultants.

STACY KEACH: For Dao, Duan and Barbara, this is just the first of many visits to Children's Hospital. Before O'Neill can decide whether or not the twins can be separated, dozens of tests must be done.

CHILD AT HOSPITAL: Hi.

BARBARA HEADLEY: Say hi. Say hi, Dao. Say hi. They only know bye.

CHILD'S MOTHER: Say bye.

CHILD AT HOSPITAL: Bye.

BARBARA HEADLEY: Bye-bye. Look! Say hi.

STACY KEACH: Two weeks after arriving in Philadelphia, Dao and Duan are settling into family life, along with the Headley's other children, Lauren and Jennifer.

DR. DAVID HEADLEY: Well, what have we got here? You want to get down and walk around? Do you? OK. You want that?

STACY KEACH: As is quite common in conjoined twins, one twin, Dao, is smaller and weaker than her sister. Even though they share a third leg, Duan appears to have more control over it. Wherever Duan wants to go, Dao must follow. If the twins are not separated, they face a bleak future. The middle leg is not growing below the knee and soon they will be unable to walk.

BARBARA HEADLEY: Yeah, well her feet also—

DR. DAVID HEADLEY: You coming back?

BARBARA HEADLEY: We're not sure.

STACY KEACH: Dao may continue to get weaker as Duan grows, increasingly becoming an appendage on her sister.

DR. DAVID HEADLEY: They don't like to be left alone still at night, and they'll sometimes cry for an hour or so before they finally go to sleep. We're really not communicating in English. It's more of a—you know, a sign language type of needs—you express your needs in some other means, and that's the way we convey a lot of what we need to do and what they want done. When we first got them, the big one didn't want me picking her up at all, and when I'd come near her, she would, you know, wave me away with her arm. The little one didn't mind, but the big one, Duan, I guess I should start calling them Duan and Dao rather than the little one and the big one. Right? There you go. Now try it. Blow. Blow.

STACY KEACH: Whether or not these playful two-year-old girls can be separated depends on sorting out which organs they share. And that, unfortunately, will mean many medical examinations.

DR. DAVID HEADLEY: There you go.

BARBARA HEADLEY: I guess ouch. Dao there's going to be an owie, owie, owie, owie, owie. One, two, three. Good girl, good girl, Dao.

STACY KEACH: Still speaking only a few words of English, the twins endure the first of many painful medical procedures. Today they've been sedated for a CAT scan. This test, like all of their care is provided by Children's Hospital pro bono.

BARBARA HEADLEY: OK. It's OK, it's OK. Shhh.

STACY KEACH: The CAT Scan is one of a series of modern imaging techniques that will allow O'Neill's team to visualize Dao and Duan's complex anatomy before contemplating surgery. Over the next thirty minutes, the CAT scanner takes hundreds of x-rays of Dao and Duan to reveal the position of the tissues and larger organs. And soon radiologist, Dr. Mahboubi, sees a problem. The spinal canals fuse just below the level of the sacrum, the bone at the base of the spine.

DR. SOROOSH MAHBOUBI: Separate the spinal canal down here, but when you're coming down, once you're below that, you can see they're sharing together. So there is only one spinal canal coming in this baby. And the other thing you notice—

STACY KEACH: Barbara is worried. Inside the bony spinal canals are the delicate spinal cords. If they are fused also, then it may be impossible to safely separate the twins.

DR. SOROOSH MAHBOUBI: And as you can see, this is coming down into the bladder—

STACY KEACH: A CAT scan cannot visualize the spinal cords, so this crucial question can only be answered with another test. The radiology reveals several other anomalies about the twins. Dao and Duan not only share a third leg, but have a fused pelvis. Dao and Duan each has a colon. The colons join together just above a common rectum. Each twin has just one kidney and urine drains into a single bladder.

BARBARA HEADLEY: You're waking up?

CT TECHNICIAN: Do you want to go to McDonald's with Mom?

BARBARA HEADLEY: Do you want to go downstairs?

CT TECHNICIAN: McDonald's, golden arches.

STACY KEACH: Until a magnetic resonance imaging can be done to investigate the spinal cords, the prospects of separating Dao and Duan remain uncertain.

CT TECHNICIAN: There you go.

BARBARA HEADLEY: Look, Dao. Yeah! Look at all these presents. My gosh!

STACY KEACH: On June 6th, Dao and Duan celebrate their third birthday. Only six weeks after arriving in Philadelphia, they're getting the hang of American life.

BARBARA HEADLEY: Look. Sing it with me, the farmer.

STACY KEACH: While they still talk to each other in Thai, they understand some English and can even speak a few words. Dao and Duan are in a sense true Siamese twins. The land of their birth, Thailand, used to be called Siam. Conjoined twins are often called Siamese twins because of two brothers, Chang and Eng Bunker who lived in the last century. Chang and Eng, who were joined at the abdomen by a wide band of skin, travelled to America where they found work as entertainers. Chang and Eng Bunker prospered, bought land in North Carolina, married two sisters and between them fathered twenty-two children. For all their success, the Bunker twins wanted more than anything to be separated and toured Europe trying to find a doctor willing to do the operation, but none would dare, suspecting that the tube that connected them contained part of the liver and important blood vessels. Aged sixty-three, they died on the same night, still joined together. Today a surgeon like O'Neill would have little difficulty separating them.

DR. JAMES O'NEILL: It's interesting. I think that the risk probably would have been very small. It probably would have been handled by taking a very, very thick ligature, or tie, and tying off the connection and then after circulation had adapted, to do a rapid separation. As most people know, the Bunker twins were never separated and when they died, they were still together.

STACY KEACH: Dao and Duan are fortunate to be born in the age of high tech medicine. But they are joined in much more complex ways than the Bunker twins. Even in the 1990's, it may be impossible to separate them without killing or crippling them. Today, Dao and Duan's future hangs in the balance. Only magnetic resonance imaging has the ability to visualize the spinal cord and reveal whether the twin's spinal cords are joined. Within a few hours, Barbara will know whether or not the twins can be separated. After examining all the films, radiologist, Dr. Larissa Bilaniuk, reaches a firm conclusion. While the bony spinal canals are fused, the delicate spinal cords inside them are not.

DR. LARISSA BILANIUK: It looks good because the cords are not joined.

BARBARA HEADLEY: They're not joined. I saw that, I was like, "Whew!"

STACY KEACH: In principle, Dao and Duan's spines can be separated without damaging the spinal cords. The main obstacle to surgery has been overcome.

BABYSITTER: Sally the camel has four humps, so ride Sally ride. Boom, boom, boom. Sally the camel has three humps. Sally the camel has three humps. Sally the camel has three humps, so ride Sally ride. Boom, boom, boom.

STACY KEACH: The twins pass a wonderful Summer, interrupted only by examinations and tests.

DR. DENIS DRUMMOND: I would guess just from looking at this that this is not going to be splittable into two.

PHYSICIAN: No, no.

DR. DENIS DRUMMOND: That you'll have one baby who could have the whole and one baby who could have the upper leg.

PHYSICIAN: Yes.

STACY KEACH: While Dao and Duan play, O'Neill and his team confront some difficult questions. Which twin should get the third leg? How should the internal organs be divided up? Dao and Duan, whose union includes the spine, pelvis, intestine, bladder and reproductive organs, present a uniquely complicated case for the Philadelphia doctors. O'Neill and his team worry about whether they can separate the twinS in one grand operation, or whether they will need to do it in stages. Dr. Luis Shut, the neurosurgeon who will divide the spines, eventually decides that it will be too dangerous to separate Dao and Duan from the front. There is too much risk of bacteria from the gut contaminating the delicate spinal cord.

DR. LUIS SHUT: So you know, really, I only need to be here, you know?

STACY KEACH: Shut thinks that a preliminary operation should be done from the back to separate and seal off the two spines and partially divide the sacrum, the place where they join. The case of Dao and Duan has reached the point of no return, for while tomorrow's operation will not separate the twins, it will weaken the pelvic ring that holds them together. For this reason, the twins will be confined to bed after surgery. This is the last day on which Dao and Duan will walk together.

DR. LUIS SHUT: The situation here is that we have conjoined twins that have two normal spinal cords. There are two complete spines, but there is only one sacrum, that is, the base of the spine. So the idea here will be to separate the two spines and give every one of the—each one of the babies half of the sacrum. The most difficult part of the operation is going to decide which nerve goes to which leg. And the second most difficult part is going to reconstruct the tube to make sure that it doesn't leak that fluid that we all have inside our spine called the cerebrospinal fluid. My incision needs to be—and then I want to go—

STACY KEACH: Having planned his incision, Dr. Shut prepares the surgical field. Despite the information from the imaging studies, Shut is unsure how the nerves leading to the legs exit the spinal cords, and he will have to be especially careful. Within an hour, Dr. Shut has exposed the spinal canals. Viewed from above, they form the shape of a "Y." The two arms of the "Y" are the spines of each twin.

DR. LUIS SHUT: This is the right twin's spinal canal, and you can see it coming down. This is the left twin's spinal canal you can see coming down. Here is the junction of the two spinal canals and dural sacs, and here it is a portion going into the sacrum, and you clearly can see small nerves here going into the sacral foramina. So the next challenge is going to be to find out what's inside the tubes and to see where the nerves are going and which one is going to get which nerve. We found it and now we are cutting it through, the point runs here like that one. We're working very fine. You can see one tube now on the right, a tube on the left, complete separated and sutured, and this is the piece of bone that now has to be split.

STACY KEACH: Shut and his colleagues begin cutting through the sacrum, the bone at the base of the spine. They won't cut all the way through today because major blood vessels lie underneath. They will leave a thin layer of bone in place that will easily come apart when Dr. O'Neill performs the main operation from the front. After four hours, Dr. Shut is finished. But for Dao and Duan, the surgery isn't over. This operation provides a good opportunity for plastic surgeon, Don LaRossa, to insert skin expanders.

DR. DON LaROSSA: The main problem in almost all of these conjoined twins is a lack of skin because when they're separated, there's going to be a big surface to which they're joined where there will be a lack of skin, and they don't have enough skin to just simply pull it over. What we're going to do today is essentially put in some balloons under the skin. They're made of silicone and they have a little tube attached to them and a small filling port. We'll put one behind this leg, and one in front of this leg. The reason being, this leg is going to go with this baby. Apparently this baby has control of this leg. But we need skin to help resurface this side of this baby after the twins are separated. So my plan would be to expand this skin and this skin, essentially build this up so that we then have enough skin to close—to take this area that I've outlined right here and bring it back like so to cover this surface and have enough skin to then bring this back together.

STACY KEACH: Once in place, the plastic balloons will be periodically inflated with saline solution, slowly stretching the skin over the coming weeks. By 4:30, the first operation is over. A critical hurdle has been passed, but Dao and Duan can't be separated until the skin expanders have grown enough skin to close the wound. This will take about three months. Following the operation, Dao and Duan are placed on forced bed rest. It is too risky to allow them to move around with the skin expanders in place, so they've been placed in a cast, with only Barney to pass the time.

BARBARA HEADLEY: Dao has an expander right here that's stretching her skin, and Duan has one right here and one underneath the center leg and she has one on her belly right here. It hurts when they expand them, but right now they don't hurt too much. They're really bored, but—but I'll tell you, they're so patient and understanding. They really have been real cooperative. There hasn't been any problems at all.

STACY KEACH: While the twins remain in the hospital for three months, David and Barbara go on with their lives as best they can. David continues working as a gerontologist in his private practice in New Jersey where Barbara also works. But all the time, their thoughts are with Dao and Duan.

DR. DAVID HEADLEY: I guess they're going to do a cystoscopy tomorrow, right? It was a hard time. When I would go to the hospital, it was often difficult to leave because whenever we would come, they'd become so attached to us that they would just cry every time we'd leave. It seems like they've been here from the very beginning. We don't treat them or think of them any differently than we do our others.

BARBARA HEADLEY: Mrs. Horner, would you like to come on back?

MRS. HORNER: Yes.

BARBARA HEADLEY: How are you?

MRS. HORNER: Good.

BARBARA HEADLEY: When they first asked us to find a home for these children, they were just children, like strangers. They didn't have a personality, they didn't have anything. And since we've gotten to know them, I mean we really love them and we really care about them and want them to do well. And they think we're their parents.

STACY KEACH: As the main operation approaches, Barbara is increasingly worried about the twins, especially Dao. Physically, Dao is getting weaker and needs feeding through a tube. Psychologically, Dao is clearly anxious about the coming separation.

BARBARA HEADLEY: Dao's having a problem, a little bit, with her identity. She's been calling Duan "Dao," and she used to call her Duan until all the surgery started. So she's having a problem with where she begins and where she ends. Where's Dao? Where's Duan? Oh my goodness. Show, what's going to happen? What are the doctor's going to do? I think they do understand and they just say, "No, no." You know, "Don't let the doctors do that." But then at times they seem like they want it, cause they'll separate the dolls themselves and then tell well Dao's going to take a walk and you know, Duan's going to play with Jennifer. So they do have a positive aspect to it. But also, they're—I think they're very scared of what the doctors are going to do, because they don't want any boo-boos as they say.

STACY KEACH: As in all the twin separations O'Neill has performed, difficult choices must be made, decisions that will critically effect what organs Dao and Duan come away with, decisions that will not only determine the success or failure of the operation, but also the quality of each twin's life afterwards. To review these difficult choices, Dr. O'Neill gathers his team together the day before surgery, radiologists, anesthesiologists, general surgeons, urological, neurological and plastic surgeons. Even for these top pediatric specialists, tomorrow's separation is unusual, the most complex they have attempted. Doctors have flown in from Thailand to observe the unusual operation.

DR. DENIS DRUMMOND: Although it's a double femur, I think it would be a great folly to try and make two legs out of this. You'd end up with two rotten legs, and my thoughts are based on the presumption that the larger twin, which is Duan, gets the leg. At any rate, the plan, I think, is to go through, either through here—

STACY KEACH: Dr. Drummond, Head of Orthopedic Surgery, has recommended all along that Duan should get the third leg, as she has most control of it. This is agreed. But where to divide the bone is only one consideration. Tomorrow, the team must separate the twin's blood vessels as well.

PHYSICIAN: I'll make it a little bit darker here, very homespun affair. But basically, to simplify the arterial anatomy, then, this is just the conjoined aorta over the partially split sacrum. There's one big iliac going to each leg and then there are two small vessels going to the—

STACY KEACH: Perhaps most complicated of all is the urogenital system.

DR. JOHN DUCKETT: The ureters are right inside the opening as a normal, single bladder. Now, then it bifurcates up here to these two segments. So—

STACY KEACH: Dr. Duckett plans to divide the single bladder into two parts, giving Duan the larger part and Dao the smaller. Although it might seem unfair that Duan, who will get the third leg, also gets most of the bladder, these decisions are made purely on medical grounds. The point is not to simply divide the shared organs equally, but to give the organ to the twin in whom it has the best chance of surviving and growing. This depends most critically on the nerve and blood supplies. The meeting breaks up, but the planning continues. What everyone fears is being confronted tomorrow with a dangerous surprise. While the doctors ready themselves for a grueling surgical marathon, David and Barbara Headley spend the last night before surgery at Dao and Duan's bedside. For three months, the Headley's have been under enormous stress, spending as much time as possible at the hospital while managing home life and work.

DR. DAVID HEADLEY: They didn't have the beanbag downstairs, did they?

STACY KEACH: Dao and Duan have been with them for seven months. The Headley's are thinking about adopting them.

BARBARA HEADLEY: Everybody's worried about them. Everybody. We've gotten thousands of phone calls from people just worried about them. And my kids are home praying, when we left. They're just easy to care about. As soon as anybody meets them, they love them.

STACY KEACH: Morning comes, and the twins wake up crying, fully aware and frightened of the ordeal to come. Today is the most important day of Dao and Duan's lives. If all goes well, before the day is out, each will become a physically separate individual. But everyone is aware this is a life-threatening operation, one or both twins could die.

DR. JAMES O'NEILL: We will start going right down the midline. We will open the abdominal cavity and see if it is reasonable to divide the intestine first. The overall plan is to attempt to do this in a fashion where it's like opening the pages of a book, or a clam shell, if you will, and that will then give us access to visualize the structures that we have only visualized radiologically, but that we know are there.

STACY KEACH: In the first operation, the sacrum was partially divided from the back. Today, O'Neill and his colleagues will operate from the front, carefully dividing the twins system by system, reconstructing organs and controlling bleeding. More than thirty people fill the large operating room. Many will be on their feet for the next fourteen hours. The skin expanders have done their work and are deflated in preparation for the first incision.

DR. JAMES O'NEILL: This here gives us enough room around the genitalia, I think. No, I could see it click. Yeah, I can feel it. And you could see it jump. What do you say, back over here?

STACY KEACH: In the first stage of the operation, O'Neill and his team open the front of the pelvis. Once inside, they carefully divide the colons just above the rectum. Later in the operation, Dao's colon will be pulled through the skin to make a colostomy.

DR. JAMES O'NEILL: May I have a small retractor please?

STACY KEACH: 11:33, four and a half hours after Dao and Duan arrived in the operating room. Everything is going smoothly, but a difficult challenge lies ahead for urological surgeon, Dr. Duckett. Dao and Duan have a single bladder. Duckett must find a way to divide it, giving each twin a part, replumbing their urinary systems.

DR. JOHN DUCKETT: Our situation is we have one bladder in a normal position with two ureters coming into the base of it and a bilobar body of the bladder on each—on each side. We're going to take off about a fourth of the bladder on the right side, and leave that blood supply with Duan. So right now, we just have to decide where to divide that bladder.

STACY KEACH: Due to its position, Duan will get the large part of the bladder and Dao the smaller part. But Dr. Duckett hopes the smaller part will grow over time.

DR. JAMES O'NEILL: And we save this pedicle over here, you've got the pedicle?

DR. JOHN DUCKETT: You've got the pedicle still?

DR. JAMES O'NEILL: No, a different pedicle. You'll need to move back a little bit, if you would, if you wouldn't mind moving. Thank you. You'll get me contaminated if you stay too close.

STACY KEACH: The bladder divided, the surgeons continue carving out the boundary that will physically define Dao and Duan. 2:17, more than seven hours into the operation.

DR. JAMES O'NEILL: If you look up at the diagram over there, there is a connection between the two aortas, and we're now dissecting out to see if we can find the right place to divide, so that's where we are at the moment.

STACY KEACH: Joining Dao and Duan are a series of major blood vessels, including a major tributary of the aorta. Tension mounts as O'Neill prepares to divide this critical vessel. Dividing conjoined twins is not about equality or fairness. O'Neill and his team have given Duan the third leg, the common rectum and the largest part of the bladder because the blood and nerves that serve these organs are principally under Duan's control. Duan, when separated, has the best chance of using these parts successfully. 5:10, ten hours after the twins enter the operating room. The critical moment approaches. All that remains holding Dao and Duan together is a thin layer of bone left in the sacrum at the base of the spine. Everyone focuses on O'Neill as he prepares to sever the last physical link between Dao and Duan.

DR. JAMES O'NEILL: OK. All right. Now I have to change—now are we—do we need to move this one? OK, so let's have a clean sheet.

STACY KEACH: Activity intensifies as the group divides into two teams, one for Dao and one for Duan. Duan's surgical team worked quickly to close the wounds. The skin expanders have done their job well and there is enough skin to make the closure. By 8:30, Duan's surgery is over. The next forty-eight hours will be critical for her. She will be closely watched for any signs of infection and hemorrhaging.

DR. DAVID COHEN: Hello.

DR. DAVID HEADLEY: Hello. How'd we make out? OK?

DR. DAVID COHEN: We're OK. She's still asleep, but why don't you say hello to Duan?

DR. DAVID HEADLEY: Honey, come over to this side. OK, she's still asleep.

DR. DAVID COHEN: Yeah, we're going to leave her sleep for awhile, let her wake up slowly.

BARBARA HEADLEY: When, how long—

DR. DAVID HEADLEY: Do you mind if I take a look?

DR. DAVID COHEN: Yeah.

STACY KEACH: Barbara and David Headley have been waiting anxiously all day.

DR. DAVID COHEN: They'll give you a call. If they don't call you in about a half hour, call them.

BARBARA HEADLEY: OK. Do you know what the number is? No?

STACY KEACH: They are relieved to see that Duan has made it this far, but await news of Dao still undergoing critical surgery back in the operating room.

DR. DAVID HEADLEY: Well he said give them twenty minutes.

STACY KEACH: Dao, the smaller and more fragile of the two twins, now has only one leg, a partial bladder and half a pelvis. She will require extensive reconstructive surgery to her bladder and colon. But today's procedure will leave her with a complete set of reproductive organs. If she survives, like Duan, she will be able to have children when she grows up. By 10:00pm, it is all over. Dao is taken to join Duan in intensive care. For O'Neill and his team, it is a satisfying moment.

DR. DON LaROSSA: It's amazing to see them, two little individuals, isn't it?

DR. JAMES O'NEILL: Yeah, I like that. Yeah. I like that.

DR. DAVID HEADLEY: You want to just wait here or?

BARBARA HEADLEY: Yeah, they said to wait here.

STACY KEACH: While the surgery is over, Dao and Duan are still at high risk. O'Neill will be watching for signs that the skin grown with the skin expanders is alive and healthy, and whether in closing the wounds the skin flaps have been drawn too tight, compromising the function of internal organs and possibly impairing breathing. Dao, in particular, is prone to infection because she has undergone extensive abdominal surgery. O'Neill and his team will be watching closely. Should any of the internal connections rupture and leak abdominal contents, Dao might be in trouble. Soon after the operation, Dao does develop a serious infection and a raging fever, but within a few days, it is under control. Ten days later, both twins are doing well physically, but psychologically, they're having trouble adjusting.

BARBARA HEADLEY: I'm going to put a pillow under her head, OK?

DUAN: Uh-uh.

BARBARA HEADLEY: Yeah.

DUAN: No.

BARBARA HEADLEY: There, Dao.

DUAN: No, Mommy. No.

BARBARA HEADLEY: No pillow for Dao? Why? Why can't she have one?

STACY KEACH: Dao and Duan are among the oldest conjoined twins to be separated, and no one's sure how two sisters joined for three and a half years will cope with being physically separate individuals.

BARBARA HEADLEY: The two of them won't acknowledge each other. We've been trying to get them to communicate or at least say hello. Once or twice they did talk to each other. It was really brief. We haven't had a chance to put them and their beds together because of all the equipment and all the—that's on their bed, and it just wouldn't be right. And Dao has a fever and she doesn't, so they don't want them to each make each other sick. But basically they seem angry at each other. When Duan woke up from surgery, she asked where Dao was, and I showed her. When Dao woke up from surgery, it was like there was a phantom person. She woke up and was screaming and flailing her arm that was where Duan was. And she was pounding on the bed with her arm screaming and turning in circles looking for Duan. So I came in the room and I quickly oriented her and showed her where Duan was and she was OK. But for about twenty-four hours she would just fling her arm over and hit the side of the bed looking for Duan. See? I just wanted to give Dao a kiss. Can I give you a kiss? OK. Can I give Dao a kiss?

DUAN: No, no.

BARBARA HEADLEY: Oh boy. No?

DUAN: Uh-uh.

BARBARA HEADLEY: OK. I'll hold your hand too, Dao.

STACY KEACH: From a Bangkok orphanage to the surgical unit at Children's Hospital, Dao and Duan have shown remarkable adaptive powers. They now face perhaps their biggest challenge, learning to live as individuals.

BARBARA HEADLEY: Within two weeks they were—they came to terms with it. Dao came to terms with it before Duan. Duan was still angry that Dao was around for a couple of weeks, but eventually, once they got out of the intensive care unit and into their own room, we could put them together, and eventually we had them each in—we put them in the same bed and let them touch and let them see each other. And then one day they just hugged each other. And that was the end—that was it. And that was the first time they saw each together—like face to face. Dao's gained a lot of weight. She's as tall as Duan now. They're exactly the same height. Her appetite is better than Duan's. Her personality's just as strong now as Duan's. She has independence, which she never had before. She talks back to Duan, which she never did before. She was always the one that was quiet and let Duan dominate. And today, physically they look more alike height, weight and appearance and emotionally, Dao now has a personality and she has a separate self, which she never had before. Duan ruled the roost. And today it's not like that. Come here. I want to ask you something.

DUAN: What?

BARBARA HEADLEY: Where was Dao? Where was Dao? Where was she on you? Right there? Right there. Come here, come here. I want to ask you something. Oh, God, please. Come here, I want to ask you a question. Do you like having Dao over here?

DUAN: Yes.

BARBARA HEADLEY: Do you like it? Do you like being over here, instead of on her? You guys. Come here, I want to ask you a question. Could you do me a—could you do me a big favor? Could you do me a big favor? Do you guys want to—do you want to give Dao a big hug? Aw, isn't that cute? You can give her a hug?

DAO: Yeah.

BARBARA HEADLEY: Come here, come here. Get over here, you're going to fall. Come on in here.

STACY KEACH: On Dao and Duan's fourth birthday, the hospital threw them a party. Over the past year, the twin sisters have won the hearts of all the doctors and nurses.

DR. JAMES O'NEILL: When you undertake something like this, your goal is to see that you can, if at all possible, come out with two complete individuals who can take their place in society and be productive. I think the other physicians have identical feelings of great gratification in seeing these children grow and develop and behave like normal children. There's no better feeling one can have than seeing that.

STACY KEACH: The Headley's did decide to adopt Dao and Duan, a huge responsibility given that the twins will require extensive medical treatment and rehabilitation. The Headley's medical insurance company may not cover these expenses, and so they plan to start a charitable fund to help pay the twins' future medical costs. Dao is learning to walk with a prosthetic, and will require many operations to further repair her urinary system. Duan also needs an operation on her leg to remove the portion below the knee that is not growing and fit a prosthetic.

BARBARA HEADLEY: You, where you going?

TEACHER: Seal.

DUAN: Seal.

DAO: Seal.

TEACHER: Good girls, good girl. Now what about this? What is this?

DAO: Uhm, a mouse.

TEACHER: It looks like a mouse. It has a long bushy tail. What is it? It's a squirrel. Do you have squirrels in your yard at home?

DAO: No.

TEACHER: No?

DAO: At my house.

TEACHER: At your house?

DAO: At my house.

TEACHER: Let's look at this one. This is a—

DAO: Star.

TEACHER: Star. Teeth together and blow. Star.

DUAN: Star.

TEACHER: Good, good. And that's one of your favorite songs that we sing is "Twinkle, Twinkle, Little Star."

STACY KEACH: With a family to care for them, these two bright children have started preschool like millions of their peers. Like the Bunker twins before them, Dao and Duan have found a future in America. And, while Dao and Duan are no longer physically joined together, they, like most twin sisters, will probably be inseparable.

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