PHILADELPHIA (CBS) – A New Jersey man is going to great lengths to help children with autism.

Twenty-four-year-old Sean Thomson loves spending time with his little cousins.

“It just feels natural for me to do it,” Sean said.

His cousins, triplets Steven, Kiersten and Ashley, all suffer from autism. For years, Sean thought about ways to help their mother, Stacey Moore.

“I was just going to try and raise money for my three little cousins. Now I’m raising money for people I’ll never meet in my life, and that’s the cool part,” said Sean.

Sean is raising money in an extraordinary way. “To know that a complete stranger is going to benefit from me running a hundred miles….” Sean said.

Yes, that’s what he said. Last week Sean ran 100 miles. In the home video, Sean’s the one in the gray sweatsuit. Some of his friends rode a bike and ran with him, from North Philly to Wildwood, New Jersey. Sean did it in 24 hours–not an easy task.

“I’m probably never going to do a hundred miles again,” Sean said.

But he did raise a lot of money with sponsors: $6000 for autism education and research programs to help his cousins and other families affected by the disease.

Stacey says Sean is an angel.

“He has my heart. It’s just a bigger space in my heart and in the kid’s hearts,” she said.

The money raised is going to the Kinney Center for Autism Education at St. Joseph’s University.

Watch the video…

Reported by Dave Huddleston, CBS 3