Little Johnny has been playing at his friend Mary’s house all afternoon when Mary’s mother brings Johnny home, and she looks very angry.

Mary’s mother says: “I caught your son playing docotrs and nurses with my poor little daughter”.

Johnny’s mother replies: “Let’s not be too harsh on them. They are bound to be curious about sex at that age.”

“Curious about sex?!” Replies Mary’s mother. “He’s taken her appendix out!”