Peter Kline will run Rock ‘n’ Roll Las Vegas to round out a 100-mile day.

The road racing medals had been draped around Peter Kline’s neck. His dresser was stuffed with running T-shirts. He even beat the clock, dropping his marathon PR from a 5:03 debut to 3:42 in a span of two years, the latter fast enough to qualify for Boston.

But at 60, something was missing.

“Before, running was all about me,” says Kline, now 62. “Running to see how fast I was. I thought, ‘There has to be a higher purpose.’”

In an epiphany, Kline found his calling. The father of three healthy boys, Kline decided he would push children with disabilities 26.2 miles. He would take youths who couldn’t walk, be their legs and turn them into marathoners.

“I thought there were kids out there, who because of some circumstance in their life, would never be able to be part of a marathon,” Kline says. “I could be their legs and shown them that experience.”

A financial advisor for Merrill Lynch who lives in Bellevue, Wash., Kline has run nearly 50 marathons, 10 of them pushing children with disabilities. This weekend at the Rock ‘n’ Roll Las Vegas Marathon and Half Marathon, he plans to stretch the challenge.

He hopes to run 100 miles in 24 hours, all while pushing children he has raced with before in a stroller.

Kline will begin his quest at 10:30 p.m. Saturday on the UNLV track. There, he’ll run circles around the track, pushing youths for 72 miles, then shove off for the Sunday late afternoon start of the marathon on the Strip.

“I think this is an incredible message about inclusion for children,” says Kline.

The man has pushed a child with cerebral palsy. He pushed a teenage boy whose legs were severed in a driving accident. He pushed a girl who was paralyzed after a tree fell on her.

Describing the marathon experiences with children, Kline says, “It changed the whole way I experience marathons. Before, it was all about me. All of a sudden, the clock doesn’t matter. I run in the back of the pack with somebody who would never enjoy the marathon experience.

“You’re needed by that child. You’re needed by their parents. The parents are turning over their son or daughter to me, a guy who sometimes they’ve never met until the day of the race. In some cases, these kids are deathly ill. The faith they have in me, letting go of their son or daughter so they can race with me, that’s incredible.

“Back-of-the-pack runners latch onto me. They’ll say, ‘If you can make it to the end, I can make it.’”

Kline remembers pushing one boy, Erik Rodriguez, through a marathon. Weeks later he received a letter from the boy’s mother. In broken English, the mother wrote something along the lines of, “Peter, you have changed our family. You have given us the ability to understand we can include Erik in things with our family.”

Now, the family runs 5Ks—Erik included.

To train for races, Kline pushes a stroller loaded with 140 to 150 pounds of weight. There’s the 60-pound bag of cement, the 45-pound and 25-pound weightlifting plates. Come race day, the man’s arms and back are as important as his legs.

From Saturday night to Sunday evening, Kline plans to push 12 children during his 24-hour journey. All 12 children will be pushed through the 26.2-mile marathon, thanks to volunteers who will be assisting Kline.

“If you have the ability to change a kid’s life and their family’s life, that’s incredible,” Kline says. “Why wouldn’t you do it?”