Alex 'Al' Keller is one of the people who first worked with The Wiggles in 1998. He's not only a sound engineer but also a musician by playing the bass guitar, acoustic guitar, cello and steel drum. He married Sonja Keller and they have a daughter named Jessica who can be seen in Pumpkin Face, Go Santa Go! and Rock & Roll Preschool. He also has a son named Jonas from his previous marriage.