The three families met for the first time on March 13 at a luncheon set up by Children's Hospital of Philadelphia

Credit: Courtesy: Kathleen Hilferty

Leta Moseley is tiny.

She’s 17 years old but just 3’8″ tall and 66 lbs. She can’t speak and she struggles with heart problems and a lung disease that can turn a simple cold into a life-threatening event.

She’s been in and out of hospitals her entire life – and for more than 15 years no one could tell her parents what was wrong with her.

In February 2013, thanks to new, cutting-edge technology that only became available in 2012, Dr. Ian Krantz, a geneticist at Children’s Hospital of Philadelphia not only solved her medical mystery – she and two other of his pediatric patients shared the same mutation on the same gene (AFF4) – he discovered a new form of dwarfism.

“We named it CHOPS Syndrome,” Krantz tells PEOPLE.

“The initials stand for the symptoms all three share: Cognitive impairment and coarse facial features; Heart defects; Obesity; Pulmonary involvement; Short Stature and Skeletal Dysplasia,” he says.

He published the results in Nature Genetics on March 2 in a paper he coauthored with Katsuhiko Shirahige and Kosuke Izumi of the University of Tokyo and CHOP genetic counselor Sarah Noon, among others.

But he didn’t just give the families a diagnosis – he gave them peace of mind.

“None of the parents carry the gene,” Krantz tells PEOPLE. “It is de novo, meaning “newly occurring” so the change happened either during fertilization or when the egg and sperm were forming.”

Leta’s mother, Lainey, says it was a relief to find that out.

“I felt incredibly guilty – like I’d done something wrong in my pregnancy or ate something or drank something,” Lainey, who’s chronicled Leta’s journey on her blog, tells PEOPLE.

“It was good to know it wasn’t my fault,” she says. “It’s a genetic mutation that’s an anomaly. It’s not something I did or I carry or that her dad and I share.”

Finding out there are at least two other families with the same disorder – Liam Hilferty, now 14, of West Chester, Pennsylvania, and Nadira Grant, now 11, of Brooklyn, New York – was “bizarrely unbelievable,” to me, she says.

“My jaw just dropped,”she says. “To find out there are two other Letas running around in the world and they’re not in Algeria – they’re less than two hours away from you.”

Part One: Solving a Medical Mystery: What’s Wrong with My Child?

That also gave the parents comfort, says Rick, Leta’s father.

“There was a feeling of happiness for Leta,” he tells PEOPLE. “She’d had so many struggles in her life and she’s got a little body. She has lots of special needs. She has communication challenges.

“So now suddenly it was like Leta was in a little club,” he says. “She wasn’t all alone.”

And Dr. Krantz is confident there are more Letas out there that just haven’t been diagnosed yet.

After the Diagnosis

The three families quickly began reaching out to each other and sharing photos.

“When I saw Liam’s photo on Facebook it was eerie because he and Leta look almost identical,” says Rick. “They looked more like each other than their parents.”

What was even wilder was Leta’s reaction to his photo.

“I showed her the picture and she looked at it, smiled and said, ‘Me,’ ” says Rick. “What’s funny is we’ll check out Liam’s Facebook as Leta’s going to bed and she still looks at it and says, ‘Me.’ ”

The same thing happened the first time the two children met at Liam’s home in November 2013.

“Leta came over and the first time they saw each other, Liam was pointing at himself and Leta was pointing at herself-like, ‘That’s me,’ ” says his mom, Kathleen.

Pretty soon they were acting like siblings, she says.

“They were fighting over potato chips,” she says. “It was so funny. Liam knows sign language and he’s yelling at her in sign. She’s trying to grab the chips. They didn’t fight until there was food around.”

The two parents also began trading notes, says Rick.

“We’re all kinda rapid fire going, ‘Look how they’re doing this. How’s the hearing? How’s the glasses? Does he keep his glasses on? How’s his breathing? How often does he do treatments?’ he says.

At the same time, he says he was “astounded” at all their similarities. So was Kathleen.

“Leta and Liam look so alike it’s crazy,” she says. “Joseph and Liam are twins and they look nothing alike.”

The same thing happened when Leta and Nadira met in December 2013 at Leta’s school in Kimberton, Pennsylvania.

“I cried because I saw so much of Leta in Nadira,” says Lainey.

“Leta seemed to be very protective of Nadira and very loving – almost like it was her little sister,” she says. “It was very sweet.”

Melissa Ashton, Nadira’s mom, agrees.

“Me and Levar, my husband, , we have this joke that they are sisters,” she says. “They look alike. The behaviors were the same and it’s so good to see that Nadira has someone she can connect with, totally identify with. It was amazing.”

The 3 Families Meet

On March 13, the three families met for the first time at a luncheon in Philadelphia arranged by CHOP.

It was hard for the parents to keep the smiles off their faces as they watched their children interact. Though they are different ages, all three are under four feet tall: Liam is 3’7″ tall and 80 pounds and Nadira is 3’3″ tall and 52 pounds.

They see the diagnosis as the first step toward a treatment or even a cure. At the very least it means no other parent with a child with this disorder will have to go through years of not knowing what’s wrong.

And since no one can tell them their child’s life expectancy, it helps them cope.

“I finally have someone to talk to who knows exactly what I’m dealing with,” says Kathleen. “And Leta’s 17. It gives me hope.”

At the end of the luncheon, the three moms gave Dr. Krantz a present – a black baseball cap with the words “Got Chops?” to show their gratitude for him not giving up on their children.

“He had this really random hunch,” says Lainey. “He saw three different families; scratched his head and said, ‘Hmm. I think these three things could be the same.’ Talk about a needle in a haystack.”

It may not be a cure or a treatment yet but it’s enough for now, she says.

“Day to day it hasn’t solved Leta’s genetic issues or made her medical problems go away,” she says.

“Her life is not going to be improved by labeling her genetic syndrome,” she says, “but it sort of offers hope and potential for future children born with the same syndrome.”

Melissa agrees.

“I’m hoping that moving on, if there’ss anyone else that’s in the same situation at least they wil have some feeling of, ‘Oh, Ok, knowing that this is what the condition is because the unknown is what’s difficult,” she says.

“Hopefully moving on there will be some treatments in the early stages that will help the children.”