LONDON-Conjoined twins have gotten the best present for their first birthday, the gift of life.

Little Erin and Abby Delaney, who are turning one-year-old in July, were successfully separated in an 11-hour surgery. The girls were joined at the top of their heads, a condition called craniopagus. It is the rarest type of conjoined twins. 

Erin and Abby, who are from North Carolina, were in excellent care. Their surgery took place on June 7 at the Children’s Hospital of Philadelphia, which has done 23 separations.

An official for the hospital said the surgery was carefully orchestrated, with monitors and equipment marked with purple and green tape indicating which was being used for which little baby.

Each detail had to be mapped out as it took a team of around 30 health care professionals in a variety of fields to complete the surgery.

The team was co-led by neurosurgeon Gregory Heuer, MD, PhD, and plastic surgeon Jesse Taylor, MD.

The team included physicians, nurses and other medical staff from neurosurgery, plastic and reconstructive surgery, and anesthesiology.

The lucky little girls are recovering in the intensive care unit.

Parents Heather and Riley never gave up on their daughters. They found out they would be conjoined just 11 weeks into Heather’s pregnancy and immediately started looking into specialized pre-natal care, according to a statement released by the hospital. Conjoined twins are extremely rare. The statistics for a fighting chance at life are incredibly slim, around half of the twins are still born, and about a third who do make it into the world die within their first 24-hours.