Four years ago in PyeongChang, Charles Flaherty was one of those improbable Olympics stories you’ll find inside any Athlete’s Village, if you look hard enough.

An Alpine skier representing, of all places, Puerto Rico – the island territory’s first Winter Olympian in 20 years – who at 7 provided the bone marrow donation that saved his three-year-old brother William’s life.

His story is getting a sequel at the 2022 Winter Games, and this time, William Flaherty is the main character.

The younger Flaherty brother, now 17, will compete in the men’s giant slalom Saturday night. He’ll do so in between surgeries, the latest of more than 20 procedures (his family has lost count) he’s had in his life.

I just look back and say, 'Thank God I made it through.'

William Flaherty

As a toddler in Cincinnati, Ohio, William was diagnosed with hemophagocytic lymphohistiocytosis, a rare, life-threatening disorder in which the immune system attacks organs inside the body. He was given a 10% chance to live.

Then came the bone marrow transplant, which brought the brothers closer than ever. It worked. William was released from the hospital 10 days later.

“I was so young that I’m fortunate enough not to remember too much of the bad stuff,” William said. “I just look back and say, ‘Thank God I made it through.’”

Several rounds of chemotherapy followed before he was declared healthy enough to join his brother in the family’s favorite activity, Alpine skiing. The sport helped William’s recovery, strengthening his bones with every run. But the next year, the Flahertys moved to Puerto Rico to accommodate their father Denis’ job, and skiing was relegated to their annual vacations to Colorado.

That was until 2013, when older brother Charles decided he wanted to pursue the sport seriously. The family hired renowned coach Sara Radamus – mother of 2022 U.S. Olympian River Radamus – to get the best out of Charles, who had a uniquely streamlined path to the Winter Olympics if he could achieve the minimum qualifying standard.

Charles was eligible to compete for Puerto Rico via residency status. But first, his father Denis had to revive the island Winter Olympics program. Charles became Puerto Rico’s first Winter Olympian since 1988, carrying the flag at the Opening Ceremony.

But in the time in between, the Flahertys faced tragedy. Denis died suddenly and unexpectedly just seven months following the 2018 Games.

“I’m super grateful that Denis got to watch Charles in PyeongChang,” mother Ann Flaherty said. “That was sort of the pinnacle of his life.”

Charles had plans to join William at the 2022 Games, but eventually chose instead to focus on an internship with SpaceX as he studies to become an aerospace engineer. That means 2022 will be William’s Olympics, and his alone. He’ll debut in the men’s giant slalom Saturday night (the first run begins at 9:15 p.m. ET, live on NBC and Peacock). He'll be the final skier down of the session, 89th of 89.

“I can’t wait to see him come down that hill and cross the finish line,” said Ann, who, because William is a minor, is able to be with him. “I don’t know how I’m going to keep all those emotion in, because I’m just so excited for him.”

Ann recently said that William will soon need surgery on his jaw, which was discovered to be severely weakened as a residual side-effect from his childhood chemo treatment. It’s unlikely to deter William. After all, nothing else has.

“There’s a light at the end of the tunnel,” William said. “Keep a smile on your face and look forward to what awaits you in the future.”