Many movies, cartoons, and television shows often depict pets in a lighthearted way, showcasing their cheerfulness and laissez-faire attitude. On the contrary, modern science suggests that pets possess a deeper level of intelligence than we ever dared to imagine, and they experience the range of feelings we once assumed were just felt by humans.

"The visible expression of grief is widespread in the animal kingdom," Barbara J. King, author of "How Animals Grieve," told Stacker. "A cat wails in visible distress after the death of her sister; a dog stops playing and eats poorly when his dog friend dies."

Dr. Carly Fox, senior veterinarian in the Emergency and Critical Care Unit at the Schwarzman Animal Medical Center, also points to an Italian study of 426 adults who owned at least one dog, one of whom died while the other was alive. The study, published in the journal Scientific Reports in 2022, found that the behavior of the surviving dog changed after the loss of a canine companion, according to a survey from owners.

However, Fox points out this reported change could easily be attributed to the owner's own emotional state. "There is a lot of anecdotal evidence for pet grief, but true scientific evidence is difficult to ascertain," Fox told Stacker. Nevertheless, it is not too farfetched to imagine one's four-legged companions going through the same kind of mourning as you.

The average number of pets owned per household in the United States is 1.5 dogs and 1.8 cats, according to the American Veterinary Medical Association's 2024 survey. These figures indicate that a number of homes have more than one pet, pushing the average above one and increasing the likelihood that many owners will experience seeing their pets mourn their missing companions.

Our four-legged companions are a central part of many families, yet the impact of their loss is often underestimated. Ollie analyzed studies and consulted experts to provide tips for helping a pet mourning the loss of another.

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