When you see Hafþór Júlíus Björnsson—better known as "The Mountain"—on screen or pulling a literal plane, it’s easy to assume he’s a freak of nature. An anomaly. But if you were to walk into a Björnsson family reunion in Reykjavik, you’d quickly realize he’s just one piece of a very tall puzzle. Honestly, the guy barely stands out when he’s standing next to his dad.
The Hafþór Júlíus Björnsson family isn't just a collection of relatives; it's a genetic masterclass in Icelandic height. We're talking about a lineage where 6'9" is "about average." But beyond the tape measure, there's a lot of heart, a fair share of tragedy, and a very famous height gap that keeps the internet obsessed.
A Dynasty of Icelandic Giants
Hafþór didn't just pop out of the ground. His father, Björn Þor Reynisson, stands at a towering 6'8". Think about that for a second. Most NBA players would be looking up at him. And then there’s the grandfather, Reynir Ásgeirsson, who is roughly the same height.
It wasn't all just "born this way," though. Thor grew up on the family farm, hauling rocks and doing manual labor. This wasn't some CrossFit trend; it was survival. His mother, Ragnheiður Júlíusdóttir, is also exceptionally tall for a woman. When you combine those genes with a childhood spent lifting literal boulders in the Icelandic countryside, you get a "Mountain."
Thor also has two sisters, Bryndís Björg Björnsdóttir and Hafdís Lind Björnsdóttir. While they don't spend their days deadlifting 500kg, they are part of that same tall-as-hell lineage. Bryndís recently made Thor an uncle, which led to some of the most hilarious photos on the internet—the world’s strongest man holding a newborn niece that looks like a small grape in his palm.
The Wife and That Famous Height Gap
If you’ve spent five minutes on Instagram, you’ve seen her. Kelsey Henson. She’s 5'2". He’s 6'9".
They met in 2017 at a bar in Alberta, Canada, where she was working as a waitress. She asked for a photo, and well, the rest is history. They got married in October 2018. People always ask the same annoying questions: How do they kiss? How do they... you know? Kelsey’s response is usually some variation of "He leans down, I reach up." Simple.
She isn't just "the wife," though. Kelsey is a fitness powerhouse in her own right. She’s the one who kept him grounded during his transition from Strongman to boxing and then back to the platform. They’re a team. You’ll often see her in his YouTube videos, basically acting as the tiny, focused anchor to his massive, chaotic energy.
The Kids: Stormur and Theresa
Hafþór has a son with Kelsey named Stormur Magni Hafþórsson, born in 2020. Stormur is already looking like he’s going to be a unit. He’s often seen "training" with his dad in their home gym. It’s kinda adorable and terrifying at the same time. You’ve got this toddler trying to lift plastic weights while his dad does reps with 400 lbs.
But Thor’s family story isn't all sunshine and PRs.
He has an older daughter, Theresa Líf, from a previous relationship with Thelma Björk Steimann. For a long time, their relationship was strained. Thor has been open in the past about the pain of not being able to see her as much as he wanted. It’s a reminder that even if you can lift half a ton, you can’t always fix family dynamics with brute force.
Grief and Resilience
The Hafþór Júlíus Björnsson family faced a devastating blow in late 2023. Thor and Kelsey announced they had lost their second child, a daughter named Grace Morgan Hafþórsson, at 21 weeks.
It was a rare moment of vulnerability for a man whose entire brand is built on being "unbreakable." They shared photos of their daughter, who they got to hold briefly. It was a heavy, humanizing moment that showed the world the "Mountain" is just a man. They’ve been very open about the grief, which has honestly helped a lot of other families going through similar "silent" losses.
What's Next for the Björnsson Clan?
As of 2026, Thor is back in the Strongman world, breaking records like he never left. But his focus has shifted. It’s less about being the "biggest" and more about longevity.
If you're looking to take a page out of the Björnsson family book, it’s not about finding a 6'8" partner. It’s about these three things:
- Consistency over Intensity: Thor didn't get strong overnight. It was years of farm work followed by decades of gym work.
- Support Systems Matter: Kelsey and his parents are at every major meet. You can’t carry the world alone.
- Vulnerability is Strength: Being open about their pregnancy loss and family struggles hasn't made Thor look "weak"—it’s made him a legend.
For the most authentic updates, skip the tabloids and follow Kelsey’s Instagram or Thor’s YouTube channel. They’re pretty transparent about the reality of living as a giant in a world built for "normal" sized people.
Check out Thor’s training app or his "Thor's Skyr" brand if you want to eat like an Icelander, but maybe don't try to lift the rocks in your backyard just yet.