KATMANDU, Nepal (AP) -- A conjoined twin who was separated from her sister during a grueling, 100-hour operation seven years ago died Tuesday at a hospital in Nepal, doctors said.

Ganga Shrestha, 8, died at the Model Hospital in Katmandu, three days after being admitted for treatment of a severe chest infection, Dr. Basanta Pant said. The physician, who has treated the girls most of their lives, refused to give details.

However, Ganga has been described as the weaker of the twins and had not made satisfactory progress since the marathon operation to separate their fused brains took place in April 2001 in Singapore by a team of 20 doctors.

Ganga and her twin, Jamuna, were 10 months old when the surgery took place. The operation was followed by people around the world and gave the doctors and the twins celebrity status.

Four years ago, during a follow-up visit, doctors in Singapore expressed concerns that the twins were malnourished, weak and needed to grow.

Singapore footed the bill for the surgery and paid for the family's travel. Doctors worked for free, and the hospital waived many of its charges.

Doctors had warned that the twins would face "some kind of disability" as they grew but were confident that the separation was successful.

CNN