A young child in Australia becomes interested in an injured red kangaroo that her rehabilitator parents are helping to treat. The kangaroo has a baby, called a joey, in its pouch. Readers will follow along as the narrator observes the development of the joey as it grows from a tiny baby the size of a cherry into an adult kangaroo--the largest marsupial in the world. Colorful photos, diagrams, and clear, age-appropriate text will engage young readers as they explore the life cycle, natural habitat, physical characteristics, diet, and behavior of these incredible creatures. The diary format models scientific observation and critical thinking, and encourages children to keep notebooks recording their own investigations into the natural world.