Spritle Racer is Rex, and Speed's youngest brother. He is always seen with the family's pet Chimpanzee, Chimp Chimp. Spritle is always sneaking into the trunk of the Mach 5 whenever Speed is with Trixie. When Speed is in a jam, Spritle and Chimp Chimp always get him out of it at the last second, and even though Speed never really thanks him for it, Spritle knows his big brother loves him, and will do anything to ensure Spritle's safety.