A little boy from League City is alive thanks to the selflessness of a stranger. A sheriff’s deputy from Oklahoma donated bone marrow to Kayden Nazzario two years ago. On Sunday, they met for the first time.

Kayden was born with an extremely rare bone marrow disorder called Congenital Amegakaryocytic Thrombocytopenia (CAMT).

As a result, his body was not making platelets. He had to undergo countless platelet transfusions as an infant.

Doctors told the family Kayden needed a bone marrow transplant.

“The chances of finding a match are so rare. Knowing that he might not have a match out there and that was his only chance at living a normal life, then none of us being a match, it was devastating. It was really hard at first,” said Shelby Nazzario, Kayden’s mother.

It turns out his match was a complete stranger in Oklahoma.

Cleveland County Sheriff’s Deputy Neil McMillin had joined the bone marrow registry in 2013.

Years went by before he got the call about the transplant.

All he was told was that he was a possible match to “an infant male somewhere in the United States.”

“Once I got the call there was no doubt about it, donating was a priority,” said McMillin. “I was able to help and he needed help. No questions about it.”

Thanks to McMillin, Kayden got the transplant he desperately needed.

After more than two years, McMillin traveled to League City to meet Kayden.

“My heart’s pounding out of my chest. Being a cop, I’ve dealt with a lot of scary things at times. This tops everything by far,” said McMillin before knocking on the family’s door in League City.

It was an emotional, moving moment for both families.

“He doesn’t know us. We didn’t know him. He didn’t have to do this. He did this selflessly,” Kayden’s mom said. “He went under anesthesia and did whatever he needed to do to help somebody who he had no idea who it was.”

McMillin recently learned he was a match for a second person. He donated his marrow again earlier this year.