They Started Playing Football as Young as 6. They Died in Their Teens and Twenties With C.T.E.

The families of five of these athletes — Wyatt, Meiko, Hunter and the twin brothers Josh and George — spoke extensively about the downward spirals, the confusing diagnoses and the heartache of loss and regret.

It is hard to imagine their childhoods without football. This is America, and football is laced into its cultural soul.

Lives spin around the game: afternoon practices, Friday night games, Saturdays and Sundays spent huddled around televisions.

Start them young in tackle football. Watch their faces as they put on the pads. Watch their helmets jiggle as they run down the field. Watch them collide with the others.

Watch them get up and do it again. And again. And again.

How dangerous could it be? They are so small. So young. So resilient. They seem so happy.

Wyatt Bramwell dreamed of playing football at the University of Missouri and then the N.F.L.

Meiko Locksley was a former college football player and the son of Michael Locksley, who is now the head football coach at the University of Maryland.

Hunter Foraker played at Dartmouth College before quitting over concerns about concussions.

Josh and George Atkinson III were twins who played for the University of Notre Dame. Their father, George Atkinson, is a former Oakland Raiders defensive back known as the “Hit Man.” His sons died by suicide less than a year apart.

All young athletes get hurt. There are times when the situation becomes scary. The crowd moans, then hushes. Coaches and trainers run out. Players silently kneel. Who is hurt? How bad is it?

There is worry, there is empathy, there is relief. The game goes on.

Those are just the injuries that get noticed. There is no counting the ones that don’t. Every smack of the head. Every jar of the brain. For some players, maybe most, they may never add up to anything serious, or maybe not for many years.

For others, they multiply quickly.

When is a battered helmet merely the mark of a gritty, hard-hitting player, and when is it a cracked shell hiding something damaged and darker?

Each athlete had his unique struggles. Most families did not connect the dots to C.T.E., with symptoms that can include impulsivity, moodiness and memory loss.

Meiko Locksley fought deep bouts of paranoia. Wyatt Bramwell was a model student in high school who became uncharacteristically rebellious. Hunter Foraker, haunted by nightmares, abused alcohol as his problems deepened. Josh and George Atkinson III had suicidal thoughts after their mother’s death.

The families shared at least one thing: a growing concern that something was wrong with their child. Was it a passing phase or an ominous sign? Was it due to football or something else?

There were desperate searches for answers. Interventions. Professional help. But these were a different kind of sports injury, not the broken bones or the torn ligaments that were relatively easy to diagnose.

In some cases, the kids themselves became worried, wondering what was wrong with their minds. They said so, sometimes to their parents, sometimes to doctors.

Sometimes in a journal or a college essay. Sometimes in song lyrics. Sometimes in suicide notes.

Wyatt Bramwell sent the most direct message, through the video that he recorded on his phone for family and friends moments before he died. All of the families in the study had that sudden, shattering moment. George Atkinson felt it twice: Josh’s death by suicide in 2018 and then George III’s less than a year later.

Amid all the struggles by the young men and their families to try to fix what they could not explain, there came the worst possible news.

Today’s athletes play in an era of heightened awareness of the dangers of concussions and of the cumulative effects of hits to the head.

It is different than 20 years ago, when most research focused on deceased N.F.L. players, including Hall of Famers, whose lives had unraveled because of damage to their brains.

Now, families of young athletes who never came close to fame or fortune are approaching researchers, donating their children’s brains in a desperate search for answers.

A positive C.T.E. diagnosis can be both illuminating and painful.

It can be a relief for a family to have a scientific explanation for the struggles of their child. It can be oddly comforting to know that symptoms may have gotten worse, since C.T.E. is a progressive disease.

But it also may raise more tangled, philosophical questions about what the families might have done differently.

Some families are haunted by regrets and what-ifs. They want others to learn from their loss. But what is the lesson?

For some, answers are hard.

The researchers behind the study of the young athletes believe the more years of tackle football that someone plays, at any age, the higher the likelihood the person will develop C.T.E.

Only a small percentage of youth football players will play in college or in the pros. But as the study shows, they can still become afflicted with C.T.E.

So researchers recommend that families delay the start of tackle football, to limit exposure.

Many of the families from the study now agree. Atkinson, the former Raiders player who still works for the team, thinks tackle football should not be played until high school. So does Kia Locksley, the wife of Maryland’s coach.

Several parents said that they cringe when they drive past fields of young children who are wearing helmets and pads and tackling one another.

What ties them all together is that their children are gone. And they don’t wish that on anyone else.