Josie Hull and Teresa Cajas opted for special pink and purple Guinceanera dresses

By Lindsay Kimble
Updated August 05, 2016 03:00 PM
Courtesy Children's Hospital Los Angeles

Josie Hull and Teresa Cajas have officially entered teenagerdom – and are so happy to celebrate with two very different and special dresses.

The girls, who debuted their Quinceanera dresses at the Children’s Hospital Los Angeles on Thursday, were born conjoined twins. Hull and Cajas were famously separated at the skull in a 23-hour procedure conducted in August 2002 when they were just over a year old.

Now all grown up, Hull and Cajas – who were adopted into different families after their Guatemalan parents couldn’t properly care for their medical needs – are enjoying their separate lives.

“I was so happy to see everybody today and I’m really excited about our [Quinceanera] party coming up,” Hull said in a statement. “So many doctors and nurses have helped us do so much and now I get to do dance competitions, sing and swim because of them.”

The special pre-Quinceanera event (the formal celebration will happen Aug. 7, a few weeks after their July 25th birthday) found the girls walking the red carpet in their pink and lavender gowns, and posing for photos.

Hull and Cajas ate cake with hospital staff and family, and visited with many of the doctors, surgeons and nurses that have aided in their post-surgery treatment over the past decade.

At their real coming of age party, Hull tells PEOPLE, “We’re having cake, candy, a photo booth and an In-N-Out truck.”

She adds, “I’m really excited about our party.”

According to the release, the girls have undergone a total of 32 surgeries at Children’s Hospital Los Angeles. (Their 2002 procedure took place at UCLA’s Mattel Children’s Hospital.)

“Because of the great care we get at Children’s Hospital L.A., they get to survive and go out in the real world and really thrive,” Hull’s mom Jenny shared. “These girls bring hope and inspiration to so many.”

She continues to PEOPLE, “It has been a more difficult road for Teresa. We’re just so glad because we were not sure the girls would make it to 15.”

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Dr. Mark Urata, a member of the surgery team that separated the twins, treats Hull and Cajas today at Children’s Hospital Los Angeles, where he is chief of plastic and maxillofacial surgery.

At the time, separation surgery was uncommon, and the prognosis for conjoined twins like the sisters was uncertain. “If one gets ill, the other could get sick too, so the statistics aren’t very strong for having a long life as conjoined twins,” Urata says. “I think the separation has been a life-altering experience for them.”

In 2012, Hull and Cajas parents told PEOPLE that although the girls have different families, they come together several times a week for physical therapy, shared meals, play dates and the pool and sister time.

While Cajas cannot speak, Hull said at the time, “You can tell [when] she’s happy. My sister and I have been blessed. We’re lucky.”