A mother tells her little boy:
- Johnny, you mustn't eat too many lollies or I'll hide the lolly jar.
Johnny asks:
- Why?
His mother says
- Because something bad will happen! Your tummy will blow up big like a balloon and then pop!
The next day at church, the boy is sitting next to a pregnant woman. He points to her belly smiling and says:
- I know what you've been doing!