Dierks Bentley and family are mourning the loss of one of the singer's oldest friends this weekend. Bentley shared Sunday (July 10) that his dog, Jake, has died.

"Rest in peace, pal," the singer writes on social media alongside a black and white photo of his buddy.

The 15-year-old dog had been battling cancer. Bentley noticed the lumps last year and put Jake on chemotherapy. The shepherd mix is almost as well-known by fans as the singer himself — he's been by Bentley's side for countless awards shows and events. Jake even attended the opening of Bentley's Country Music Hall of Fame exhibit earlier this year.

“Jake’s been with me through every phase of my career, since before I had a publishing deal … before I even had a gig, really,” Bentley told attendees at the June opening. “When I got my first gigs downtown, he’d be waiting there in the windowsill. He actually wore out a little spot in the couch where he’d wait for me. I’d come home real late, and he’d be there sitting in the window, putting in his time. Those were his years of grinding, sitting in the window waiting for me.”

A song on the star's new Black album is dedicated to the furry friend who had been by his side since long before he was famous. Bentley says he can't get through the final verse of "Can't Be Replaced" without crying. It goes:

"For 15 years, right by my side / From a single man to three kids and a wife / Friends come and go, but when it comes to Jake / There's just some things that can't be replaced." 

Dierks Bentley Writes Heartfelt Song for His Dog, Jake

See Jake and More of Country's Cutest Pets 

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