A little boy walks into his parents bedroom to see his mom on top Of his dad bouncing up and down. The mom sees her son and quickly dismounts. Worried about what her Son has seen she dresses and goes to find him.

The son sees her and asks "What were you and daddy doing?"

The mother replies "you know how your daddy has such a big tummy and sometimes I have to get on top of it to help flatten it."

Your wasting your time" said the boy.

Why is that?" asked the mother puzzled.

Well when you go shopping the lady next door comes over and gets on her knees and blows it right back up.