TOO young to know how grave their situation is, a pair of one-year-old twins have been happily 'high-fiving' the stream of doctors and nurses who look after them.
Unlike normal twins, the two girls are joined at the hip and abdomen, share some organs and have only three legs between them.
Doctors in Singapore are now deciding whether or not it is feasible to separate the conjoined twins, who were brought here by their parents from Indonesia.
A rich Indonesian sponsored their trip, after Indonesian doctors baulked at separating them.
The conjoined twins arrived here last month. They went through tests conducted by doctors at Mount Elizabeth Hospital, who also consulted surgeons from KK Women's and Children's Hospital.
A KKH spokesman said: 'A multi-disciplinary team of specialists reviewed the twins and concluded that it was technically possible to separate them.'
The twins were moved to Gleneagles Hospital earlier this month, where they are under the care of a different team.
A spokesman for Parkway Group, which owns both Mount Elizabeth and Gleneagles hospitals, said that doctors were still evaluating the case.
The girls' parents are a poor couple from the countryside. Little is known of the sponsor, except that he had previously paid for treatment here for other Indonesian children suffering severe disabilities.
'Smart kids,' a source said, referring to the twins.
They have been taught how to 'high five' - holding up their hands and slapping their palms against someone else's as a greeting - and can't stop doing it with health-care staff.
Separating the twins will present a tremendous challenge requiring multiple operations. It is likely to be done in stages over a period of time.
The main challenge is to ensure that their lower bodies, below the waist, will work after the operation. This is because their intestines are joined, and lead to only one anus between them.
To complicate matters, the anus and the vagina share the same exit. It is smaller than normal, so bowel movements have been difficult.
Doctors are now trying to flush the girls' system because it is clogged, making it hard to see clearly inside the joined abdomen.
They need to know if the two have only one bladder, which would mean a second one would have to be created using some of their intestines. The substitute would not be as good as the real thing, but at least it would work.
Doctors are also keen to find out if each child has her own uterus and ovaries, and if these organs are working properly.
Each child will likely end up with just one leg because the third leg lacks a proper knee or hip joint. But tissue from this leg can be used to patch up their tummies after the separation.
The pelvic bone, now fused, will also have to be split.
To make things more perilous, one of the girls has a hole in her heart. If she should suffer a heart attack during the operation, both would likely die.
As daunting as the separation sounds, the prospects of both surviving if they stay together are dim.
The twin with the abnormal heart could succumb to heart failure, which would kill both.
Doctors could patch up the hole, but think it's safer to separate them first. Heart specialists who have examined her said the hole can be corrected.
Singapore doctors successfully separated Nepalese twins Ganga and Jamuna Shrestha in 2001 and Korean twins Min Sa Rang and Ji Hye in 2003.
But an attempt in 2003 to separate Ladan and Laleh Bijani from Iran failed, with the adult twins dying on the operating table.