Sharing a photo of the sweet dog, the star wrote: "Today we said goodbye to our lovely rescue dog Banjar. Farewell old friend. Sleep well."
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Before long, many of his fans had rushed to the comment section to share touching messages of their own, and no doubt Bill felt comforted reading through their lovely notes.
Bill shared the sad news on Twitter
"So sorry Bill, it's heart breaking isn't it? We're gearing up to say goodbye to our own small boy, he's so poorly," wrote one.
"Sorry for your loss Bill. It’s so hard to say GOODBYE to our pets. Their Love is so precious. We lost our Sandy a year ago. But we have thankfully lots of memories and videos to keep us going. Not the same but it helps," added another.
A third commented: "Very sad when you lose a fur family member, we had to go through it in August, so my thoughts are with you all at this tough time. Please take comfort in the fact you gave your dog a home and love, which they may never have had and your dog would have loved you for that chance."
Bill is partnered with Oti Mabuse
It's set to be a busy few weeks for Bill, who is currently competing in this year's Strictly alongside professional dancer Oti Mabuse, and his hectic schedule will no doubt be a welcome distraction following the sad family news.
Bill and his wife Kristin Bailey are doting parents to their 14-year-old son Dax, and the tight-knit family live together in London.
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