Toocheck makes Nikolas' meals extra healthy with "secret ingredients" mixed into his foods like protein grains and pureed vegetables.
Nikolas finished his first marathon in just under six hours, walking a little bit along the way.
"The whole idea of this is to complete them, not to compete in them," his mom said. "He's competing in them to raise money for a cause."
The super-athletic 9-year-old is always on the go and cheered on by sister Thea, 14, who their mom says is as passionate about writing as Nikolas is about running. She's just published her second book, "Night Crawlers," available on Amazon.
When asked what his favorite sport is, Nikolas laughed and said, "That's really hard."
"I think baseball, hockey, football and running are all tied," he said.
He's "not exactly sure" what he wants to be when he grows up, but would like to play sports. He says the Olympics are not out of the question.