Family friend Bill Jones tells PEOPLE in an exclusive interview that Braman's "pride" kept him from sharing his diagnosis

Former NFL linebacker Bryan Braman passed away at 38 years old on Thursday after battling a rare form of cancer. Braman was diagnosed with the aggressive disease in February and had undergone several surgeries in Seattle, according to a GoFundMe set up to help him pay for the expenses of the treatment.

Super Bowl-winning linebacker Bryan Braman, who played for two teams across seven seasons in the NFL, has died aged 38 after a battle with a “very rare form of cancer,” his agent confirmed to CNN Sports on Thursday.