Conjoined twin boys sharing a heart, torso, arms and legs died in an Atlanta hospital on Friday, a day after being born, their parents said in a Facebook video.
The birth of the twins was a medical rarity, as many such babies do not survive delivery.
"I am so sad to say that my sons passed away today at 5 o'clock," Michael Hamby said in the tearful Facebook video that he and his wife, Robin Hamby, of Alabama posted late on Friday. "They fought long and hard."
The twins died at Children's Healthcare of Atlanta at Egleston, the parents said. They had been transferred there from Northside Hospital in Atlanta.
Conjoined twins occur once every 200,000 live births and most do not survive, according to the University of Maryland Medical Center. About 40 to 60 per cent are stillborn, and about 35 per cent live only one day.