Fuller House Stars Mourn Cosmo the Dog: 'Say Hello to Comet for Me'

Cosmo, the beloved dog from Fuller House, has died after experiencing complications from surgery. He was 4 years old. The show's official Instagram channel confirmed the news of the golden retriever's death on Monday.

"We're sad to share that the Fullers' faithful dog Cosmo, who grew up on our set, passed away after complications from surgery," the Fuller House account announced alongside a snapshot of Cosmo as a puppy. "There will never be another quite like our boy."

Cosmo was first introduced in Season 1 as the newest addition to the Tanner-Fuller brood. He was also revealed to be the great-grandson of Comet, the Tanner family's dog in the original series. (Comet was portrayed by Buddy, who died in 1998.)

Elias Harger, who plays D.J.'s (Candace Cameron Bure) middle son, Max, Max on Fuller House, created a video tribute to the dog he shared so many scenes with and revealed that he learned that the dog passed away shortly before production on the series came to an end. He learned the news from his adult co-stars.

"Two weeks before the end of Fuller House, Candace [Cameron Bure], Andrea [Barber], and Jodie [Sweetin] sat with me at the end of the work day and told me the horrible news," Harger said. "Cosmo had died suddenly from a complication with surgery. He was only 4 years old. I was heartbroken. To honor him, I held his photo during the final curtain call, and they announced his name along with the rest of the cast because he deserved to be there. And I believe he probably was there in spirit."

Harger also remembered the good times he shared with Cosmo, saying, "We were puppies together on Fuller House. In the beginning, he had so much energy, just like me. Just like me, he liked to play. It was sometimes hard to get Cosmo to pay attention and stay on his mark, and I had to be careful not to distract him during a scene. But he grew into a seasoned actor -- in fact, we both learned to control our energy on set. We might have acted together, but our friendship was no act."

Sweetin also honored the Fuller House pet, writing, "As you may have heard, our beloved Cosmo has passed away. He had gone in for surgery and suffered complications. Our little Cosmo was always such a good boy ... Say hello to Comet for me, buddy."

Bure added, "I imagine he's playing with Comet right now. 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."

The official Instagram account for Cosmo, run by his owner, addressed the news of his passing with some heartfelt words of remembrance.

"To say that Cosmo was an incredible dog does not even begin to capture how truly magnificent he was. He entered my life when he was 10 weeks old and melted my heart immediately. He was beautiful, smart, loving, gentle, happy and extremely talented. He would pull me on set with his tail wagging because he truly enjoyed working," Cosmo's owner wrote. "In my 26+ years of being a professional animal trainer Cosmo was one that took residence in my soul and nothing will ever replace him. He loved playing ball with his Golden brothers Lunar & Rocket, chasing bubbles and working with the wonderful cast of Fuller House. Many treasured experiences and memories of him and truly blessed to have had him in my life. Everyday working with and living with him was pure joy."

Fuller House returns to Netflix for the second half of its fifth and final season in 2020.

Seasons 1-4, along with the first half of Season 5, are currently available on Netflix.

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