Al Roker pens moving piece about his special-needs son defying expectations

Al Roker is one proud dad.

The "Today" co-anchor, who appears on the May cover of the inspirational magazine Guideposts, writes that he's more proud of his son Nick than most will "ever know."

"The obstacles in this kid’s way were things that might have tripped up many others," Roker says of his teenager with special needs. "Not Nick, not even with the disabilities he was born with."

Roker, a father of three, says he and wife, ABC News correspondent Deborah Roberts, could tell "right from the beginning" Nick "would be up against a whole different set of challenges" than his siblings.

"He wasn’t developing as fast as he should have, not holding our fingers as tightly, not always meeting our gaze, not as quick to crawl," Roker writes. "At three, he hardly talked and could barely walk."

"Now that he’s 17, I can tell you that, yes, he’s somewhere on the spectrum and maybe obsessive-compulsive," Roker adds. "But those labels can be frustrating; they don’t begin to describe who Nick really is."

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Nick, Roker says, began improving after seeing speech, behavioral and occupational therapists.

"We enrolled him in a program at a school to suit his needs, watched him make friends, signed him up for tae kwon do – at his insistence – and took him to Sunday school," Roker writes. "Nick blossomed, far more than Deborah or I could have ever expected, given his original iffy prognosis. In tae kwon do, you have to master systematic sequences of moves to progress to the next level. Turned out that all those repetitive drills were just the thing for Nick. Where his OCD nature can be a drawback in some situations, it was a strength here."

So much so that Nick achieved black belt status.

Letting the world know who his son is, Roker writes: "Nick is a hard worker; he’s got a great sense of humor; he’s outgoing and a good swimmer; he’s developing a pretty good top-of-the-key basketball shot. He takes chess lessons a couple times a week, and he does okay. He’s also very affectionate – like his grandfather – and full of love to share."

Roker also reminds readers that medical professionals can be off with their prognoses, just as TV weathermen can flub a forecast.

"All sorts of specialists can tell you about limitations for this and that," he writes. "Nick never got that message."

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This article originally appeared on USA TODAY: Al Roker pens moving piece about his special-needs son defying expectations