Upon landing on Earth, Krypto is a fully grown dog, possessed of superpowers similar to those of Superman's (since all Kryptonian life-forms gain superpowers from exposure to a yellow sun, such as Earth's sun). Later, Krypto is adopted by Kevin Whitney, a 9-year-old boy, with whom Superman arranges for him to stay (as Superman himself is often too busy saving the world to take care of him).