Yoyo is a singing pup. He can howl to any, tune which is probably why Sumalee is his perfect person, as they share a love of music. They make a pretty good and unusal duet. When they try to place Yoyo in his new home, which was right next to Rebound's house, Sumalee's mother locked them out. A dispute between Agatha and Sumalee's mother made it nearly impossible to place Yoyo. Sumalee tried to show her mother of Yoyo's singing ability, but Agatha interrupted. Later Sumalee's mother reviled she loved dogs, but didn't want her daughter to get distracted in her violin lessons. When Sumalee and Yoyo made music togather, Sumalee's mother allowed her daughter to adopt Yoyo.
- Yo Yo was named after the cello player Yo Yo Ma.