Jonus is one of Grandpa and Caillou's Daddy's friends. He lives on a ranch and has horse named Lucky. In the episode "Caillou's First Wedding" he gets married to Kristen. Although he appears in only 4 episodes he is considered a main character by the producers of the show. In addition to the 4 episodes, Jonus also appears in Caillou's Holiday Movie, But is named Jonah instead of Jonus.