The weatherman shared several videos and photos of his boy - who has special needs - and his wife, Deborah Roberts, taking part in running races for charity and it was clear that emotions were running high.
Al captioned the first post: "My boy, @nick.roker155 is taking part in the @achilles_international #resilencerelay in spite of #elsa lashing the northeast. #runnickrun."
WATCH: Al Roker shares exciting news live on-air
He proudly videoed him and cheered him on as he completed two races despite the nasty weather conditions.
Al added: "Way to go son," in the caption of one clip and Deborah couldn't help but comment either. The ABC journalist wrote: "So proud of him," and a fan noted: "@debrobertsabc you and @alroker are like the proudest parents on earth! So nice to see."
It wasn't just Nick's mum and dad who were offering their congratulations either. Fans flooded the comments of all the posts with kind words, calling him, "awesome," and, "inspiring".
Nick and his family were incredibly proud of his achievement
Nick, who is the youngest of Al's three children, is "somewhere on the (autism) spectrum and maybe obsessive-compulsive," the TV star previously told Guideposts magazine.
He added: "But those labels can be frustrating; they don't begin to describe who Nick really is."
Nick ran with his mum Deborah
Al doesn't deny it can sometimes be hard but that he is continuously admiring his youngest. "Do I get frustrated with my son sometimes? You bet," Al wrote.
"But then I remember my dad, how understanding he was. And Deborah reminds me that I have to show my son not only that I love him but that I like him as well. More than that, I admire him."
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