The Season 23 Bachelor shared the news on social media on Wednesday alongside a slideshow of photos of them throughout the years. The pictures showed Sniper and Colton cuddling together, them sitting on the beach and by the pool, and Sniper in a living room. He wrote, “Today i said goodbye to Sniper. he was my boy, my buddy and my best friend: i want to thank you for always being there for me. 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.”

Colton’s caption continued, “for finishing my left overs. for taking the blame of so many farts when Cassie and i started dating. for always looking at me with love in your eyes. i love and miss you already buddy. i promise to be the man you think i am. everyday.”

Many of Colton’s Bachelor Nation friends sent their condolences in the comments. Blake Horstmann wrote, “Oh man so sorry bud! He was an awesome dog.”

Ashley Iaconetti added, “NOOO I’m so sorry!! He was so loved and lived a great, long life!”

In December, Colton posted a picture on Instagram of the two of them sitting and smiling together. He described Sniper's impact on his life, writing, "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."

Colton's girlfriend Cassie Randolph also shared a tribute to Sniper. She posted a photo of them sleeping next to each other and quoted actress Hermione Gingold, “‘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.’”

Cassie’s caption went on, “Thank you for being the best furry friend to @coltonunderwood 🐾 There is definitely a hole in our hearts today. We love you, Sniper.”

Sniper played a big role during Colton's season, especially when he and the women traveled to Denver for dates. Colton brought Sniper with him to Commons Park, and from there, Colton, Sniper and Tayshia Adams wandered around the Mile High City, stopping for ice cream and to see the sights.

See some of Colton and Sniper's sweetest photos below.