Before Simpson was involved in the Timon & Pumbaa show, he was an actor and screenwriter. Though his roles were minor, he was involved in two films, Mistress and Something of Mine. Alongside Karey Kirkpatrick, he wrote the animation screenplay for The Rescuers Down Under. Since then, he was written several episodes of the Timon & Pumbaa show, providing the lyrics for the song "Alone Together."