A pair of 4-year-old conjoined-twin girls have been separated after undergoing 16 hours of surgery in Utah, but they face a long road to recovery, doctors said on Tuesday (August 8, 2006) Kendra and Maliyah Herrin were born with their bodies joined at the abdomen and with a common pelvis. They shared a kidney and a liver while each controlled one leg. "We'd just like to formally announce that we have two separate little girls," their father, Jake Herrin, told reporters at Primary Children's Medical Center in Salt Lake City. Details of the girls' conditions were not released, and the family declined to reveal personal information about their anatomies. Maliyah will be placed on dialysis until a kidney transplant can be found. The twins were hospitalized several weeks ago so that doctors could begin stretching their skin. A child psychologist also prepared them mentally by giving them conjoined-twin dolls. The surgery is the first known separation surgery attempted on twins with a shared kidney. Conjoined twins occurs when an embryo fails to completely separate within two weeks of fertilization. The condition is rare, once in every 50,000 to 100,00 live births and is most common in female than male twins. Most conjoined twins survive only a few days.