Nine-year-old boy breaks mountain climbing record

Tyler Armstrong, a 9-year-old California boy, broke a mountain-climbing record when he became the youngest person to scale the Aconcagua Mountain in Argentina, which at 22,000 feet high is the tallest peak in the Western and Southern hemispheres.

“I think it was just super, super cool and amazing that I got to reached the summit and no other kid younger than me got to look around at that site,” he said of his accomplishment, which he achieved on Christmas Eve.

There's a reason this young man knows his way around hiking gear. When he was just seven, he reached the top of California's 14,500-foot Mount Whitney. Then, at age eight he climbed the 19,000-foot Mount Kilimanjaro in Tanzania.

“I came back from Mount Whitney, I walked up to my dad and said, ‘I want to do something bigger,’” he said. “We did Kilimanjaro. After Kilimanjaro, about a month later, I asked him, ‘Let's do something bigger.’ Then we went to Aconcogua.”

The climbs require months of dedicated workouts. His father and highly skilled sherpas have been with Tyler literally every step of the way -- all of them well aware of the dangers.

“On one side, you'll be walking on glaciers, so there's ice,” he said. “And there's probably a 1,500-foot drop. There's rocks on the bottom so you could get really injured. So you really have to be careful.”

Tyler’s father, Kevin Armstrong, told CBS News’ Carter Evans that there’s a “certain level of danger,” but the professional guides said that “Tyler is acclimated, he’s physically fit. He can do it.”

Tyler says he's using his climbs to bring attention to Duchenne, a type of muscular dystrophy that affects young people. He's already raised thousands of dollars for research.

“I kind of got that connection. How they can't walk but I can,” he said. “And then I kinda wanted to help them, so one day they can hike with me.”