The twins were born in Texas last April and were welcomed by parents Elysse and John Eric.
The parents were told that their twin girls would be conjoined and when they were born it was found their shared the same chest wall, lungs, pericardial sac (the lining of the heart), diaphragm, liver, intestines, colon and pelvis.
A team of more than 26 clinicians, including 12 surgeons, six anesthesiologists and eight surgical nurses who assembled at the Texas Children's Hospital operated to separate the 10-month-olds.
The 26-hour surgery was the first time twins conjoined at the chest and abdomen in this way had been separated successfully.
And now their mother Elysse says she can't thank the surgeons enough for giving her daughters the chance to live separate lives.
She said: "We know how much planning and time went into this surgery and we are so blessed to be at a place like Texas Children's where we have access to the surgeons and caretakers that have made this dream a reality.
"We also want to express our gratitude to all of the people that have prayed and provided support to our family over the last 10 months."
Dr Darrell Cass, paediatric surgeon said: "This is the first time a separation surgery for thoraco-omphalo-ischiopagus twins with this particular configuration has been successful.
"This surgery was not without its challenges with the girls sharing several organ systems. Our team has been preparing for this surgery for months and we've done everything from working with our radiology experts to build a 3-D model of their organs, to conducting simulations of the actual separation surgery."
The girls are now being cared for in the hospital's paediatric intensive care unit, where they will recover for the next couple of months.
