Walter "Walt" Crane (John Mahon) is Martin's brother. He appears only once, in an episode in which he and Martin meet again, only to become separated again by the end of the episode. In the episode "Author, Author" when Frasier and Niles are having a fight, Martin tells them a story about a dispute he once had with a partner. His first words are "Now, I never had a brother..." However, the story that Martin tells the boys turns out to be a lie, which he reveals to Daphne after the boys make up and leave.