There is a little boy and a little girl in the woods. The little girl asked the boy, "What is a penis?" The boy replied, "I don't know." At that time he hears his mum calling him for lunch. He goes home and eats his lunch. Then he sees his dad on the couch. He goes up to his dad and ask him, "What is a penis?" The dad whips his out and says to the boy, "This is a penis, as a matter of fact this is the perfect penis."

The boy leaves to go find his friend and brings her to the woods. The girl again asks him what a penis is. He whips out his penis and says to her, "This is a penis, and if it was two inches smaller it would be the perfect penis!"

Source: Penis Jokes