NEW YORK (CBSNewYork) — Doctors on Long Island performed the first-ever operation on triplets born with a rare skull condition.

In January, the Howard triplets — Hunter, Jackson and Kaden — underwent surgery at Stony Brook University Hospital to repair a condition called craniosynostosis, where their skulls did not form properly.

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“You could tell that their heads were a little bit malformed,” their mother, Amy Howard, 38, of Center Moriches, said. “It was really extremely scary thinking about your 8- or 9-week-old baby going through surgery.”

Craniosynostosis occurs in 1 in 2,000 births.

But doctors said the chance of this occurring in triplets is one in 500 trillion. It’s particularly unusual because they are not all identical.

“We worked out the probability of maybe on in 500 trillion to see a set of triplets the looked like these three,” Dr. David Chesler, Stony Brook Medicine, Assistant Professor of Neurosurgery said.

The condition is not only a cosmetic issue but could restrict brain growth. It’s not uncommon, but in triplets it’s extraordinarily rare — only two of them are identical.

Doctors at Stony Brook explained that the children’s skull fused too early in utero — that’s supposed to happen later in life. Their growing brains then pushed their skulls into abnormal shapes.

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“When you look from the top he has an almost almond of wedge shaped head, that’s now gone. Three months later it’s nice and round,” Dr. Chesler said.

The babies will have to wear helmets for the next few months as they recover, but then they will lead normal lives.

“They don’t mind the helmets, the surgery went great, I don’t even think they really were in too much pain,” Howard said.

The new parents are grateful their boys got a life changing head start.

“That was my main concern, was it going to cause brain damage, or I was worried about his eye sight, but it all turned out great,” Howard said.

Already the boys are all smiles and full of life.

Kaden is described as the laid back one, Hunter the talker and Jackson is the tough one.

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The Howards said the triplets were conceived without the help of fertility drugs.