Jason Kelce's Beloved Dog, Winnie, Dies

Jason Kelce's beloved dog, Winnie, has sadly passed away ... and the Kelce family is heartbroken over the loss, with his wife writing in an emotional social media post that she's "lost part of my soul."

It's unclear how the pooch passed ... but Kylie Kelce said on her Instagram page Thursday night the pup "is at peace" now.

"When I was in high school I had a folder on my desktop labeled 'Gods gift to earth,'" Kylie said in an IG post. "It was images of Irish Wolfhounds that I had collected from Google. I had fallen in love with the breed when I was a young and never let my fascination with them fade. It all lead me to Winnie and holy s*** did she live up to the hype."

"I love you, Winn," she continued. "You will always be my first born child."

Travis Kelce sent out his condolences in the comment section, writing, "You [gave] Winn an amazing life Ky!!" The Chiefs star's ex, Kayla Nicole, sent her support with a comment too.

Winnie played a huge role in the Kelce family ... she was the "flower girl" at Jason and Kylie's 2018 wedding. She was also mentioned on Jason and Travis' "New Heights" podcast often ... in fact, the brothers just brought her up on a recent episode when comparing her to animals Travis had seen on his Australian zoo date with Taylor Swift.

Winnie and the Kelces' other dog even had their own Instagram page.

"She was everything I had hoped for in a wolfie," Kylie said in mourning the dog's passing, "and more."