Conjoined Infant Twins, Connected at Waist Separated in Long Surgery

Girls were born connected at the waist.

— -- A pair of conjoined babies sharing several internal organs were separated today in 12-hours surgery, according to hospital officials.

Sisters Ximena and Scarlett Hernandez-Torres were born connected at the waist, sharing a colon and bladder -- a 1 in 50 million chance -- according to the Driscoll Children's Hospital. Last night, the girls underwent surgery to be separated at the hospital, where they have been treated since birth.

“We are so pleased that this complicated procedure went smoothly,” pediatric surgeon, Dr. Haroon Patel, said in a statement today. “The success of such a rare and challenging operation like this depends on having a skilled team of professionals working together, and I thank our great personnel for their hard work.”

The girls have never been out of the hospital, their mother, Silvia Hernandez, told ABC News through an interpreter. She hoped the operation would allow her to finally bring her daughters home, she added.

Although the girls are only 11 months old, Hernandez can already see their different personalities forming.

"Scarlett likes to dance, sing and she smiles a lot," she said. "Ximena is most of the time sleeping but she smiles a lot."

The girls were born as triplets with a third sister, who is not conjoined. Hernandez said in an earlier interview that her big concern is that the newly-separated sisters will have difficulty walking but that she is hopeful.

"I do have to believe in God's will, that everything will be fine," she said. "And he will be there in the day of the surgery and he will make a miracle with them."