Lupo was a gift from Kate's parents, Michael and Carole Middleton, in 2011 from a litter of English Cocker Spaniels that they bred, according to The Mirror. He was originally a companion for Kate for the long stretches of time she was alone when Prince William was away serving as an RAF pilot in Anglesey early on in their marriage.
It has been suggested that Kate named Lupo, which means wolf in Italian, after her paternal great-grandmother, Olive Christiana Lupton, according to The Daily Mail.
The beloved family pet was also a deciding factor in how Prince George got his name. As the royal couple was making their decision, they devised a game in which the potential names were written on paper and scattered through their home. The slip that Lupo chose would be the child's name.
The spaniel, who was featured in the early photos of the prince, caused a bit of trouble for locals in Berkshire four days before his human brother was born.
In July of 2013, as Kate was due to deliver George at any moment, lore has it that the fire department was called out to rescue the pup who had gotten his head caught in a fence at the couple's Bucklebury Manor estate — they weren't home at the time. It ended up being a bit of a wild goose chase for the squad, according to E! News.
"Our crew got to the manor but were told as they arrived at the gates that the dog, which had got its head stuck, had been freed just a few moments earlier so their services were not needed," the chief of the Royal Berkshire Fire and Rescue Service reported at the time.The family's grief has been felt worldwide as dog and pet lovers shared condolences with the couple and sent prayers of peace for Lupo.
"So sorry did your loss... animals are not pets they become family," commented one person.
"So sad. Especially first family dog. They are our hearts on the outside," wrote another.
Others included George, Charlotte and Louis in their thoughts as well.
"I remember well the photos of such happily glowing newlyweds with their new puppy. Now you have this beautiful family. I'm sure the children are so very sad," expressed one person.
"I'm so sorry. I'm sure this is hard for all of you, especially the children," another follower penned.