The ancient Egyptians mourned their cats by shaving off their eyebrows. Cats are thought to have been worshipped by some ancient Egyptians and possibly associated with deities because cats hunted many of the creatures — such as vermin and insects — that threatened Egypt's food supply. By killing their prey, cats were credited by Egyptians with saving their civilization from starvation. When a cat died, its Egyptian human family would mourn and bury it in a ritualistic manner by mummifying it and burying its body with milk, mice and other items that the animal was thought to need in the afterlife.
More about ancient Egyptians and cats: