Prince William and Kate Middleton Mourn the Death of Family Dog Lupo: 'We Will Miss Him So Much'

Kensington Royal/Instagram Prince William, Kate Middleton and dog

Prince William and Kate Middleton are mourning the death of their family dog.

The couple announced on Sunday that their beloved dog Lupo, who had been a part of their family for nine years, died the previous weekend.

"Very sadly last weekend our dear dog, Lupo, passed away. He has been at the heart of our family for the past nine years and we will miss him so much. - W & C," they wrote on social media, alongside a photo of the adorable black cocker spaniel.

Kate's brother James Middleton, a noted dog lover, also shared a touching tribute to Lupo, who shares a connection to a number of his own canine companions.

"It is with great sadness that Lupo, the beloved dog of my sister Catherine and her family has passed away. Lupo was the son of Ella, brother to Zulu, Inka & Luna," James, 33, wrote. "Nothing can ever prepare you for the loss of a dog. For those who have never had a dog, it might be hard to understand the loss. However for those who have loved a dog know the truth: a dog is not just a pet; it is a member of the family, a best friend, a loyal companion, a teacher and a therapist."

"For most, the loss of a dog is, in almost every way comparable to the loss of a Human loved one," he added, noting that "the news about Lupo brought a wave of emotions flooding back" from when he lost his first dog in 2017.

Continuing, he wrote, "There isn't much of a rule book on how to grieve for a dog, but I've said a prayer, lit a candle and taken Ella (Mum) for a long walk to spend time remembering Lupo. Rest in peace Lupo. Tilly & Mini will be waiting for you. You will always be remembered and your legacy will live on forever. Good Boy 🐾."

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Michael Middleton/Kensington Palace/Getty Images Kate Middleton and Prince William with son Prince George and family dog Lupo

William and Kate first welcomed Lupo into their family back in 2012, about a year before the birth of their first son, Prince George.

Years later, it was revealed that the royal couple got their cocker spaniel to help them at a difficult time, when William was about to head to the Falkland Islands for a six-week-long deployment.

"When Prince William was away in the Falkland Islands, he went for dinner with some good friends of ours in the Air Force, and he was saying how difficult it was for Kate because he was leaving for six weeks. It was when they'd just got the Spaniel to help her with the time apart," said Natalie Bressani, who was a guest at a 2018 Christmas party at Kensington Palace for Royal Air Force families separated from their loved ones.

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Lupo has previously starred in several family photos, including an early photo of George, now 7, with his parents.

In honor of George's third birthday, the royals released several sweet photos of the chubby-cheeked prince playing with the family pet.

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Matt Porteous/PA Wire Prince George and family dog Lupo

Dogs have long been cherished members of the royal family.

Meghan Markle and Prince Harry adopted a black labrador named Pula in 2018 shortly after their wedding — and the pup even crashed one of their Zoom calls earlier this year.

Queen Elizabeth has also had many faithful canine companions over the years, although the last of her corgis died in 2018.