Thursday, the 18-year-old from Long Beach, California, along with her dad David, climbed to the top of the world's tallest peak.
At 29,000 feet, she phoned home.
"My mom asked her how was she doing, and she said, 'I'm tired'," her brother, Ted Larson, remembers. "That's an understatement."
Her older brother says it was the dream of her lifetime.
"She has an incredible amount of perseverance, and once she sets her mint to it, it gets done," he says.
Samantha has now climbed all of the elusive 'Seven Summits,' the highest mountains on each continent, including Mount Kilimanjaro in Tanzania and Mount Elbrus in Russia.
She joins an exclusive club.
"It's amazing at any age," says Phil Ershler, and he should know. Ershler was the first American to scale the North face of Everest in 1984, and he's written several books – the latest with his wife Susan, his climbing partner.
"I would bet if you ask Samantha and her father, they would tell you they were in it together – it wasn't one of them summitting or the other," Ershler says. "They wanted to take that final step to the top of the world together."
Everest is perilous. While more than two thousand have reached its peak, over 200 have died trying.
Samantha put off her freshman year at Stanford to climb Everest.
"I always think she's going to be doing exciting things," her brother says.
Samantha's next feat is making it back to the East coast in time for her brother's college graduation.