(FOX 11) - It's more than just a birthday party for sisters Josie Hull and Teresa Cajas, it's a celebration of life. With the odds stacked against them, the girls have made it to 15-years-old.
"We're so grateful for the 15th birthday it's just a miracle that the girls survived," Jenny Hull, Josie's mom, said. "And not only survived, they've thrived through this."
In 2001, the girls were born in Guatemala conjoined at the head.
A year later doctors at UCLA performed the complicated surgery to separate them. Josie and Teresa shared parts of their brain and blood vessels.
Since they're separation they've been under care of Dr. Mark Krieger, Chief Neurosurgeon at Children's Hospital Los Angeles.
"I've known them personally for 12 years and that's just an incredible feeling," Krieger said. "At the time we had no track record on this, we just didn't know how cranial twins would survive as they progressed through life."
Despite a small chance of survival Josie and Teresa beat all the odds.
They turned 15 on July 25, and they're throwing a big quinceañera to celebrate the milestone.
"Just celebrating our lives and surviving and we can't wait for our party," Josie said.
The twins met their doctors at CHLA to say thank you for the care over the years. They have had more than 30 surgeries since their separation.
They also showed off the party dresses they plan to wear in their favorite color.
"My sister is purple and I'm pink because we just love the colors," Josie said.
The sister's, who were adopted by different families after their surgery, still see each other often and share a special bond.
Josie, who attends high school and is an avid tap dancer, has more advanced cognitive abilities than her sister Teresa, but she's including her in all the party planning.
They're most looking forward to singing and dancing with all their friends.
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