Rusty is a cat that often appeared in the Butler household in early episodes. He can be seen in several Season 1 episodes and season 2 episodes.
Many things about the cat is unknown such as its breed or where they got it from. It was most likely purchased from a pet store or they may have even had it from someone who could no longer have it. As for the breed it could either be a Tabby, Ginger or a Persian, which are popular breeds.