( CNN ) -- `` Sometimes you can forget about the preciousness of life , '' hospital spokesman Allen Poston thumbed onto his Blackberry after peering into an operating room where a team of 15 doctors and medical staff separated conjoined twins in six hours in surgery . Two-month-old twins Preslee and Kylee Wells required surgical separation . `` I 'm standing here in the operating room looking at the exposed beating heart of Preslee Wells , '' he wrote as he walked the halls at the Children 's Hospital of Oklahoma University Medical Center . On Monday afternoon , 2-month-old Preslee and her conjoined sister , Kylee , rolled onto their own backs for the first time , he said . Poston , who updated friends and relatives on the surgery with constant posts from his hospital blog , snapped photos of each girl and showed them to friends and family who had been in the hospital waiting room since early Monday . The news of the operation 's success prompted a gush of emotion , breaking the silence that had once filled the room , Poston said . After two months of waiting , the two girls were surgically separated . `` We waited because we wanted the organs to get a little bigger , a little stronger , '' Poston had told CNN over the phone earlier Monday . `` The primary concern was cardiac connection . '' After cardiac imaging , doctors determined there was `` very little [ cardiac ] connection , '' but they remained concerned about a `` liver bridge '' connecting the twins . That bridge , Poston said , posed the greatest operational risk because of its dual use by the twins . Born October 25 in Oklahoma City , Oklahoma , to Stevie Stewart and Kylie Wells , the twins are being monitored in the hospital 's neonatal intensive care unit . They are listed in critical condition . `` Today , they leave the OR in two different cribs , one following the other , still close in proximity , but might as well have been a mile apart , '' Poston wrote . `` And that is exactly what everybody was hoping for . ''
2-month - old Lilly and her conjoined twin , Kylee , were in there for two hours . They rolled onto their own , for the first time Monday , spokesman said . They are currently being monitored in a hospital 's neonatal intensive care unit .