Granny Beaver

One day, a little boy goes to his grandmother's house. The little boy asks his Grandma, "Grandma, can I jump into the shower with you?", and the grandma replies, "Sure, why not?"
So than they jump into the shower together, and the little boy looks down at his grandmother's vagina, and asks, "Grandma, what's that?" and his grandmother says, "Oh that's just my beaver", and the little boy says, "oh ok".
So later, the little boy is back at his mother's house, when he asks if he could jump into the shower with his mother. His mother says, "Sure, of course." While in the shower, the little boy looks down at his mother's vagina, and asks, "What's that?", to which his mother answers, "Oh,well thats just my beaver, why do you ask? " and the little boy says, "Oh because grandma has a beaver too, except I think it's dead because its tongue hangs out."