Former San Francisco 49er Jason Hairston was found dead Tuesday in his California home, according to reports.

On their website, KUIU, the hunting company Hairston owned, wrote that the 47-year-old “took his own life” at his home in Dixon. Hairston’s family has requested donations be made to fund CTE research at the Boston University Concussion Legacy Foundation in his honor.

According to KOVR, Hairston had returned from a hunting trip with Donald Trump, Jr. days before his death.

Trump wrote on Instagram in light of Hairston’s death, “You were and will continue to be an inspiration to all outdoorsmen and women for generations to come. Thanks for the friendship and the memories buddy. I’m going to miss you. R.I.P.”

The ex-linebacker died by suicide while possibly battling a CTE he sustained during his time in the NFL. In 2016, Hairston told CNBC that he suffered from symptoms consistent with the condition.

“I played linebacker, and the way I played the game, I led with my head. I played the way they tell us not to play now,” he revealed.

The Mayo Clinic describes chronic traumatic encephalopathy as “brain degeneration likely caused by repeated head traumas.” As a result, the rare condition is believed to be more common in people who play contact sports. CTE can only be diagnosed following a post-mortem examination of the brain.

Hairston’s official cause of death hasn’t been revealed.

[Featured Image: Jason Hairston, Donald Trump, Jr./Instagram]