Born in the English Lake District in northern England, Kavanagh first found his passion for performing and acting at the age of six when he began singing lessons and joined a local children's theatre group. He continued performing locally and at the age of nine he acted in Arthur Miller's All My Sons at the Theatre By the Lake where he portrayed the American character Bert. Later, at the age of 11, Kavanagh began a two-year stint in Billy Elliot: The Musical in London, where he played Billy's best friend, Michael. During his time in Billy Elliot, Brad was featured on the original cast recording of the show. From 2006 until 2010, Kavanagh worked extensively in children's TV. He recorded and filmed three music videos for the Disney Channel in the UK and appeared as Dylan in the short-form series As the Bell Rings. He appeared in behind-the-scenes features for movies such as Up, A Christmas Carol and Hannah Montana: The Movie and was a Kids TV reviewer for Sky Magazine. In 2008, Kavanagh was nominated for a children's BAFTA award for "Breakthrough Talent of the Year."He is self-taught on the drums, piano, guitar and bass and he loves to writes and record his own songs at home in his spare time.