One in 500 Trillion: New York Triplets Are First in the World to Undergo Surgery to Fix Rare Skull Condition: 'We've Been Blessed,' Says Dad

"They're happy, well-adjusted babies," says Dr. David Chesler, the triplets' surgeon. "They're making all of their developmental milestones."

There’s no doubt that Hunter, Jackson and Kaden Howard look adorable in their tiny little helmets.

But those helmets are there for a very serious reason — the 6-month-old triplets were born with craniosynostosis, a rare birth defect that causes a baby to be born with an abnormally shaped head.

They underwent laparoscopic surgery at Stony Brook University Hospital in Stony Brook, New York, to repair their skulls on January 5 and 6, at just 11 weeks old, and were unveiled at a news conference there earlier this week. The triplets have to wear the helmets 23 hours a day, seven days a week for the next next few months to ensure their skulls heal properly.

Stony Brook University Hospital

That’s not all.

They are the first known triplets to ever have this condition, according to their surgeon, Dr. David Chesler, an assistant professor of neurosurgery at Stony Brook, who heavily researched the case history to be sure.

“What made this so special was not so much the craniosynostosis,” he tells PEOPLE. “It was that we had a set of triplets where all three of the triplets had craniosynostosis, That’s what made the situation so rare…the probability is on the order of one in 500 trillion.”

And, nearly four months post-surgery, they are doing “outstanding,” he says.

“They’re making all of their developmental milestones,” he says. “And from a cosmetics standpoint their outcomes are great. They have almost normal-sized heads at this point. Aside from the helmets you wouldn’t know there’s a problem. Overall, they’re happy, well-adjusted babies.”

Stony Brook Children's Hospital

Their proud parents, Amy and Mike Howard of Center Moriches, New York, couldn’t agree more and said their babies don’t even seem to mind the helmets.

“I take them off at night before their last bottle,” Amy, 38, tells PEOPLE. ‘They get their heads washed then they go back on and sleep in them. Honestly, they don’t seem to mind the helmets at all. The first week they were a little fussy with them but now I take them off and put them back on no problem.”

Overall, being a parent to triplets is ‘hectic,” the parents say, but “we wouldn’t change it for the world,” says Michael, 41, a plumber/mechanic.

Amy agrees.

“They’re adorable,” she says. “It’s wonderful.”

She just went to the store by herself for the first time, she says.

“I had a lot of people laughing, saying, ‘Oh my gosh. She has three,’ ” she says. “You do get reactions for sure…We’re a spectacle when we go out.”

Adds Michael: “They want to know why they’re wearing the helmets.”

Stony Brook Children's Hospital

The parents say they could not be more grateful to their doctors.

“We’ve been blessed throughout this whole thing,” says Michael. “It’s just been an amazing, amazing experience.”