Gwen Stefani Announces Death of 18-Year-Old Family Dog

Blake Shelton and Gwen Stefani are mourning the loss of their beloved dog, Betty ... who died after 18 years with the family.

Gwen shared the heartbreaking news on Instagram Saturday ... writing, "It's with the heaviest hearts that we share our sweet Betty has gone to heaven." She added that Betty "made us all smile for 18 years" and said they'll "miss her forever."

Gwen thanked Betty for all the love and joy she brought into their lives ... ending the post with a butterfly and heart emoji.

Blake and Gwen married in 2021 and and have been together since 2015 ... meaning Betty had been around longer than the pair has been linked.

Betty was 18.