Billy Rose is the fairly quiet boy who is last to join the rocket boys, a year or so after the group is founded. In their class in school, Billy lives in Snakeroot Hollow. His persistence in asking to join is what leads the rocket boys to accept him. His excellent eye site and ability to run fast means he can track and find rockets easily after they have blasted off. When the rocket boys shoot off Auk XXII-A, which breaks the mile barrier, Billy chases it. He comes running back across the creek holding it high over his head, while the crowd cheers. When the boys shoot off Auk XXIII, it is Billy's sharp eyes that spot the rocket before anyone else. Billy goes to college and, like Sherman, Quentin, and Sonny, becomes an engineer.