The royal household of Prince William and Kate Middleton suffered a devastating loss over the weekend. The family dog, Lupo, has passed away, and the couple is extremely sad that a part of their family has gone so soon.

Kensington Royal announced Lupo's passing on their Instagram last Sunday, uploading a photo that showed the lovely cocker spaniel looking at the camera longingly.

“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 photo was captioned.

Lupo has been a part of the Cambridge family for over nine years now. The dog was a wedding gift from Kate’s parents and has been part of the many milestones they have reached together.

Kate’s brother, Michael, also sent his condolences to her sister and uploaded another photo of beloved Lupo on his personal Instagram. Michael is extremely saddened as well with the passing of Lupo as his own three cocker spaniels are Lupo’s siblings.

The couple has often mentioned their dog on several occasions, on interviews, and even during their tour. Lupo has also been photographed in events that were very important to the couple.

According to a story shared by the Duchess of Cambridge, their lovely dog played a big part in choosing their first child’s name. William and her apparently laid out several pieces of paper on the floor and Lupo picked out George.

An adorable photo shared by Kate on their Instagram showed Prince George celebrating his third birthday and sharing his ice cream with Lupo.

Back in 2013, Prince William was asked what his priorities in life were at the moment. With George's birth, the second-in-line to the throne answered that he is concentrating on his wife, George and of course Lupo.

Many of the fans of William and Kate have come to their side and sent their own message of farewell and condolences on their Instagram post.

The royal pair have no other pet in their household. Lupo was more like a family to them, as explained by a close source to the pair, and they treated Lupo as such.

William and Kate also chose to keep the reason for Lupo’s passing private, just between them and their children, but it is believed that it was old age that caused it.

We are sending our condolences to His and Her Royal Highness, Prince William and Kate Middleton.