Little Johnny walks in on his grandmother having a shower. He points and asks curiously, "What's that? His grandmother replies "Oh! That's my beaver."
The next day, little Johnny walks in on his mother having a shower. Again, he points and asks curiously, "What's that? His mother replies, "Oh! That is my beaver."
Little Johnny looks confused, and says, "Grandma has one of those too, but I think it's dead because its tongue was hanging out."