Adrian Peterson has faced a lifetime of personal tragedies, running hard through each one

Adrian Peterson is one of the most popular players in the NFL, one of the most dominant, and sadly, one of the most tragic.

The 2012 league MVP has run through pain since he was a boy, and his latest anguish may be the most unfathomable. His 2-year-old son died Friday after an alleged assault by an acquaintance of the child's mother. Peterson has said he'll play Sunday, which may surprise some who don't know his story and his resilience.

Peterson has never gone long without extreme difficulty. His older brother and best friend, Brian, was killed by a drunk driver when Peterson was 7. It happened 5 feet in front of him. His father, Norman, was arrested and sent to prison for laundering money when Peterson was 13. Peterson kept running, all the way to stardom as an Oklahoma Sooner, even though his father couldn't see him play in person until he was a junior in Norman. On that emotional day, he broke his collarbone. Then, on the night before his appearance at the NFL combine in 2007, Peterson's half-brother was murdered. Peterson was up through the night praying, and still he went through every drill the next day. He ran a 4.3 in the 40-yard dash.

On he went, bursting into the NFL and awing Minnesota Vikings fans with his breakaway runs. Life seemed so easy for Peterson on the field, as he made Pro Bowl after Pro Bowl until pain caught up to him in a literal sense: he tore two ligaments in his knee in the second to last game of the 2011 season.

The spirit never waned, though. There was never "Why me?" or even a trace of bitterness. He just kept going, apparently unburdened and unbothered, rehabbing and winning the league MVP in 2012 in what is one of the most memorable NFL seasons ever. He returned to his home state in December to play the Texans, a game the Vikings won, and he rented out two suites at Reliant Stadium for his family from Palestine. They gathered in celebration of what Peterson had done, but they insisted they were not surprised. They knew he'd come through. He always had.

And now this.

[Related: Sports world reacts to death in Adrian Peterson's family]

It's hard to imagine anything more unbearable than the loss of a child – especially one who is so young, just discovering the world and speaking his first words of love and wonder. A parent never feels there's enough time to spend with a child; Peterson had less than three years with his son.

His decision to play, or not play, is not to be judged. As anyone who has grieved knows, reality doesn't always set in immediately; sometimes it takes weeks or years. Peterson, unfortunately, has grieved more than most.

"I'll be ready to roll, focused," Peterson said about an hour before the news broke of his son's death. "I will be playing Sunday, without a doubt."

If he plays, it would fall in line with his whole life story. It seems as though Peterson has run only faster and harder with every setback. He remains open, accessible, candid, even when most superstars (and common folk) would put up walls. He even smiled Friday at his locker when asking for privacy; many people wouldn't say a word.

"Football is something I'll always fall back on," he said. "It gets me through tough times. The guys in here, that's what I need. … I'm able to release a lot of my stress through this sport."

Peterson then said what many of us believe: we're given only what we can handle.

If that's the case, it seems this man can handle anything.