A baby kangaroo is called a "joey." This term is used for the young of several marsupials, but it is most commonly associated with kangaroos. Joeys are born incredibly small and underdeveloped, continuing their development in their mother's pouch. As they grow, they spend more time outside the pouch before eventually becoming fully independent. Kangaroo joeys are often seen peeking out of their mothers' pouches, and they rely on their mothers for warmth, safety, and nutrition during their early life stages.