Prince William and Kate Middleton are mourning the death of their English cocker spaniel, Lupo.

On Sunday, the Duke and Duchess of Cambridge announced on the Kensington Palace Instagram account Lupo passed away last weekend and shared a photo.

“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,” the caption read.

Kate’s brother, James Middleton, went on to share several photos of Lupo and revealed the dog is from the litter of a dog that was owned by their parents, Carole and Michael.

“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. He was 9 years old,” he wrote in a lengthy post.

James Middleton said losing a dog can take an emotional toll on a person, and a family needs to be able to grieve. “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,” he wrote.

The British Royal Family has a history of being dog lovers, especially Queen Elizabeth, who reportedly treats her beloved Corgis like royalty. The monarch has been a fan of the breed since 1933 when she received a Corgi puppy as a birthday present.

Over the years, Queen Elizabeth has continued to own dogs from the breed that are reportedly looked after by two footmen. The dogs also have their meals made fresh each day, according to Darren McGrady, a chef who worked as a chef at Buckingham Palace for 15 years.

McGrady revealed the dog’s meals would mostly consist of beef, chicken, rabbit, liver, rice and cabbage.

“The most important part of the meat was everything had to be cut into a fine dice … to be sure there were no bones at all in the meat,” he said.

“Imagine if any of the dogs were to choke on the — I’d be in real trouble.”

Kate Middleton, Prince George, Prince William, Lupo
Prince William and Kate Middleton got Lupo in 2012. Pictured: Middleton, Princes George, William, Lupo in the garden of the Middleton family home in August 2013 in Bucklebury, Berkshire. Getty Images/Michael Middleton-WPA Pool