Bryan Braman, a former linebacker for the Houston Texans and Philadelphia Eagles, passed away on Thursday at the age of 38 after battling a rare and aggressive cancer, as reported by his agent.

According to a GoFundMe page created to assist with his medical bills, Braman had been receiving treatment, which included multiple surgeries, in Seattle after being diagnosed with cancer in February.

Agent Sean Stellato confirmed Braman’s death Thursday, noting that Braman had two daughters, ages 11 and 8.

“People noticed Bryan’s large stature, but it was matched by the size of his heart,” Stellato shared with KPRC 2 in Houston. “His positive spirit and authenticity resonated with everyone. That was what made him truly special.”

“It’s hard. I feel like I lost my firstborn. This kid, he gave me his bed every time I came to Philadelphia. He would threaten me if I didn’t stay with him. That’s something I’ll always cherish. My heart hurts today.”

The GoFundMe for Braman raised more than $88,000, with former Texans star J.J. Watt giving $10,000 and other former teammates also contributing.

“Rest in Peace brother,” Watt wrote on social media. “Gone far too soon.”

The Eagles and Texans also shared their remorse over Braman’s death.

“During his four seasons in Philadelphia, Bryan was a loyal teammate, a supporter of the community, and a valuable member of our Super Bowl LII-winning team,” the Eagles said in a statement. “More importantly, he was a devoted father who passionately loved his family and everyone around him. We extend our deepest condolences to Bryan’s family and all who are grieving his loss during this difficult time.”

Said the Texans: “We are deeply saddened to hear about the passing of Bryan Braman. Our thoughts and prayers go out to the Braman family during this difficult time.”

An undrafted free agent out of West Texas A&M, Braman played seven seasons in the NFL, from 2011 to 2017. He won a Super Bowl with the Eagles after joining the team for the playoffs, blocking a punt in the divisional round. The Super Bowl LII victory was Braman’s final NFL game.

“You look at his journey and beating the odds to make it to the NFL after going undrafted,” Stellato said. “Not only making it, but producing and becoming a world champion, he had a real hard journey. In life, we all run this race. To die at age 38, the game of football and his family are hurting today. He was a staple for what football and underdogs are about.”