"When you know that you have few memories to make with your kids, you want to make priceless ones," Weimer told NBC News.
Once news of the costumes spread, Ryan began receiving requests from parents around the world asking if he would transform their children's wheelchairs into "magic."
The Weimer family project became a hugely successful nonprofit, called Magic Wheelchair. The group has made costumes in which wheelchairs have been transformed into a Mario Kart, a SpongeBob boat, a "Frozen" ice castle and a Teenage Mutant Ninja Turtles van.
"Giving families and kids those experiences that we've been able to have year after year, it's awesome. I love it,” Weimer told BuzzFeed News last year. "My kids are seen as superstars and not looked at with sympathetic eyes or sadness."
Teams of volunteers in communities nationwide help build the incredible costumes and create unforgettable moments for children during Halloween. It takes hundreds of hours and thousands of dollars to make children's dreams come true through the project.
"When we have challenges and trials and hard times, those are the things that define us," Weimer told NBC. "It doesn't matter your circumstances, you can still make beautiful things ... and it's great to see other people get behind that."
Magic Wheelchair made eight costumes for children last year, two in Georgia and six in Oregon.
Weimer said he doesn't want Magic Wheelchair to make the costumes for Halloween only. He told ABC News that the group wants children to "roll in (the decorated wheelchairs) all year round" and to even "go shopping with Mom in a dragon."
"It's not a cure," Weimer, who has also worked as a nurse, told Buzzfeed. "I wish I was smart enough to come up with something like that. It's a cure for a day. It helps them forget. It helps other people see them as kids, and not just a kid in a wheelchair."