OKLAHOMA CITY - It is hard to tell 1-year-old twins Hartlyn and Everlee apart.
"They're smart, they're happy, they're healthy," said Khalie Perez, the twins' mother. "They love exploring."
Before Hartlyn and Everlee were born, first time parents Khalie and David Perez found out their unborn daughters were conjoined at the abdomen.
The couple was scared and uncertain about to what to expect.
"We went home when we found out about them, and looked up every possible statistic and story," says Khalie. "I probably read them ten times a piece."
As soon as Hartlyn and Everlee were born on July 8 of last year, doctors had to immediately operate to separate them, a grueling task.
"Trying to figure out how to put two babies asleep who are joined and have a common blood supply is very important and sometimes difficult," says Dr. Cameron Mantor, who led a team of 20 specialists at OU Children's Hospital to safely deliver, and separate the girls.
The separation surgery required surgeons, nurses, anesthesiologists and obstetricians who had to work together to insure the safety of the twins, and their mother.
"It's not only a technical feat to get those logistics put together, but then accomplish it, and once you accomplish the separation, you still have two children who need to be operated on," says Mantor.
Despite the challenges the medical team faced, the separation surgery was successful.
Khalie and David were thrilled to take their baby girls home.
"There have been some obstacles of course, but they've overcame, and they're thriving," says David. "They're doing really well."
Hartlyn and Everlee had to overcome some additional hurdles like more surgeries to correct organ placement in their abdomens.
Khalie and David decided to celebrate the twins' first birthday by reuniting with the team of specialists and support staff at OU Children's who helped the two darling girls get their start in life.
"Just to have the hope the doctors here provided, and the optimism, and the care that they've shown the girls," says Khalie.
The Perez's are grateful to the staff at OU Children's, and hope to pass along their optimism to other parents who might be going through difficult medical issues with their children.
"We just hope that they continue to be an inspiration for everyone, and provide hope for other families with any kind of medical challenges that their kids might have," says Khalie.
Dr. Mantor says as many as 50 percent of conjoined twins never make it to delivery, so little Hartlyn and Everlee are beating the odds every day.