Said Patriots coach Bill Belichick: "My heart goes out to him and his family."
The Philadelphia Phillies held a moment of silence for Garrett Reid before their game against Arizona.
"I really feel for him," Phillies manager Charlie Manuel said. "I'm going to send him a message that I'm sorry. I've always had a lot of respect for Andy."
Andy Reid, a father of five, took a leave of absence from the Eagles during the 2007 offseason to spend more time with his family.
Reid is in his 14th season in Philadelphia. He's led the Eagles to nine playoff appearances, six NFC East titles, five conference championship games and one Super Bowl loss.
"We've been with Andy for a long time. He's always been strong for us; we're going to be strong for him right now," Eagles general manager Howie Roseman said. "As a father and a friend, we're all hurting."
Roseman broke down in tears after announcing Garrett Reid's death and was consoled by head athletic trainer Rick Burkholder.
Teammate Nnamdi Asomugha called the younger Reid "part of our football family, our extended family, our immediate family, so it's a very tough time for us."
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