Glenn Frey's recent death has left Bob Seger mourning the loss of a lifelong friend.

As Seger told Billboard in a statement made after Frey's Jan. 18 passing, the duo had remained close for decades after bonding during their early years as professional musicians in Detroit. "I knew him for 50 years," said Seger. "He was a great kid. I always kind of thought of him as my baby brother, a little bit. He was f---ing brilliant. He was a joy to be around. I always looked forward to seeing him. It was always memorable. He had an amazing sense of humor and was just smart, whip-smart."

In a separate interview with the Detroit Free Press, Seger revealed that even though Frey's death caught the world by surprise, his declining health had been a concern for some time — and he'd spent the months leading up to his death being attended to by a team of physicians hired by the Eagles' longtime manager, Irving Azoff.

"He was in a coma, and he'd come out, but then he couldn't breathe. They'd put him back into the coma," said Seger. "They were trying like hell to keep him alive. He'd been at Columbia University Medical Center since November. Irving pulled every ace out of the hole — he had the eight best specialists working on Glenn. About a month ago, they had to throw up their hands."

While reminiscing about his and Frey's younger days with Billboard, Seger noted that as far as he could tell, Frey never lost his love for music — or his appreciation for where his career had taken him.

"Every time I saw him in the last 10, 11 years, he was so grateful to the fans," Seger recalled. "The first thing he'd say to me — normally he'd start with a joke or something — but then he'd say to me, 'Isn't it amazing, Bob, we're still doing this at our age? I am so grateful that these fans keep coming out.' And he meant it, every word. He was definitely sincere."

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