Zach Roloff and wife Tori of Little People, Big World were heartbroken over the loss of their dog, Sully, in 2017. The pup was only three years old. Sully was often featured on the show, causing many viewers to fall in love with the reality television pet star. Now fans of the show are wondering what led to Sully’s early passing.

Sully was a Bernese Mountain dog Tori drove about six hours to meet. Tori recalls being nervous to get a dog, but knew something was missing from her life. Although she wanted to meet him before she decided on anything, it was love at first sight. Sully was the dog for her. She first introduced her new dog to the Instagram world on March 28, 2014, with a photo of her with the pup on her lap and a caption that read: “My new best friend.” After that, Tori’s feed began to fill up with images and videos of the fluffy guy.

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According to The Sun, the pup died in March 2017 of cancer. Sully had liver cancer that spread to his stomach, and finally infected 75% of his body. A few days after Zach and Tori found out, Sully passed away peacefully at their home. Tori explained, under a photo of the dog’s paw, that the family spent his last five days “spoiling” and “loving on him as much as possible.TLC captured the heartbreak the Roloff family felt from the loss of Sully. An episode showed them crying as they buried Sully on the Roloff farm next to three other family dogs. The couple expressed their sadness, explaining they were hoping the dog would make up the family of their dreams and take care of their new baby. Take a look at a tribute post form Tori to Sully below:

In the weeks following their loss, Tori continued to post tributes to Sully on Instagram. A close-up image of the puppy’s snout was accompanied by the words, “There are still some moments where the pain is unbearable. Where I swear I’m going to walk through the door and you’ll be there wagging your tail with your favorite stuffy in your mouth.” Tori also reminisced in a post featuring her and a younger-than-1-year-old Sully on the day she took him home. She said her furry friend taught her how to love, be silly, and be responsible. Each post included the hashtag #inspectorsullivan.

One year after the pup’s death, Tori took to Instagram to remember her beloved family member. She posted two images: one of Sully wearing a handkerchief with the word “Brother” on it and the second of a waterfall. The caption read, “I can not believe it has been a year since we had to say goodbye to one of our very best friends. Sully STILL comes up in our conversations almost daily. These two pictures were taken years apart and I like to think the second is how Sullivan is spending his day every day.” That same year, the family got another Bernese Mountain dog named Murphy. Zach and Tori are also parents to their son Jackson and daughter Lilah.

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Source: The Sun, Tori Roloff