232. "Superman: The Story of Superman, Junior", "Congo Bill: Three Dives to Doom", "Tommy Tomorrow: The Riddle of the Space Rainbow"

Dr. Morton Kirk, believing that Earth was doomed to perish when a giant planet threatened to collide with it, sent his young son Johnny off in a rocket, intending to place him on another world. But Superboy saved the Earth, though he was unable to find Johnny Kirk, and the dying Dr. Kirk left him a last request: that if he found Johnny, he would become his legal guardian.