Bachelor Star Colton Underwood Mourns Loss of Dog Sniper: 'Thank You for Always Being There'

Colton Underwood is saying goodbye to the pet who helped him through his “darkest times.”

On Wednesday, the former Bachelor star, 28, shared the sad news with his followers on Instagram, posting a slideshow of sweet photos with his dog Sniper, as well as a heartfelt farewell to the companion.

“He was my boy, my buddy, and my best friend: I want to thank you for always being there for me,” he wrote in the caption, “For getting me through some of the darkest times in my life. For always making me smile no matter what was going on in life.”

Underwood went on to share the more humorous ways Sniper factored into his life — including in his relationship with Cassie Randolph.

“[Thank you] for finishing my leftovers. for taking the blame of so many farts when Cassie and I started dating,” he joked. “For always looking at me with love in your eyes.”

He concluded: “I love and miss you already buddy. I promise to be the man you think I am. everyday. 🐾♥️”

RELATED: Former Bachelor Star Colton Underwood Says His Dog Helped Him with ‘Depression’ and ‘Anxiety’

Randolph, 24, also shared an Instagram tribute to the late dog, writing that there is a “hole in our hearts,” along with posting a photo of herself curled up under the covers with Sniper.

“‘To call him a dog hardly seems to do him justice, though in as much as he had four legs, a tail, and barked, I admit he was, to all outward appearances. But to those who knew him well, he was a perfect gentleman,'” she wrote. “Thank you for being the best furry friend to @coltonunderwood 🐾 There is definitely a hole in our hearts today. We love you, Sniper ❤️”

The supportive partner also commented on Underwood’s post, writing, “❤️😔 love you and Snip so much.”

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In December, Underwood opened up about how he found solace in Sniper while struggling with depression and anxiety, calling the pup his “best friend.”

“These smiles say it all,” he wrote at the time on Instagram. “This dude doesn’t know how much he has helped me in his 14 years of life (103 in dog years) – through depression, anxiety and stressful situations having Sniper by my side has been the best remedy I could have ever hoped for.”

He concluded: “Love you buddy, can’t wait to see what this next year has in store for us♥️🐾 my best friend.”