Dec. 17 (UPI) -- The Fuller House cast is mourning the death of the show's beloved dog.
Cosmo debuted as a puppy in Fuller House Season 1, which premiered in 2016. The dog was a descendant of Comet, the original family dog from the ABC series Full House.
Bure, who plays D.J. Tanner-Fuller on Fuller House, said Cosmo died of complications from surgery.
"Our sweet boy Cosmo is now running around in doggie heaven. I imagine he's playing with Comet right now," she wrote. "Cosmo has been in Fuller House since the start and we are heartbroken that he passed away during surgery complications. You'll be so missed love bug."
Sweetin, who plays Stephanie Tanner, confirmed the news Monday.
"As you may have heard, our beloved Cosmo has passed away. He had gone in for surgery and suffered complications," she said. "Our little Cosmo was alway such a good boy and our hearts are [broken]. Say hello to Comet for me, buddy."
Barber, who plays Kimmy Gibbler, shared a pair of photos of Cosmo on Instagram.
"There is a Cosmo-sized hole in our hearts. We miss you, sweet boy," she wrote.
Fuller House is a sequel spinoff to Full House, which had an eight-season run from 1987 to 1995. The show follows an adult D.J. (Bure) and her three sons (Michael Campion, Elias Harger and Dashiell and Fox Messitt).
Netflix released Part 1 of Fuller House's fifth and final season this month. Part 2 will premiere on the streaming service in 2020.
The Fuller House cast celebrated the show's wrap with karaoke at a party in November.