One night a little girl walks in on her parents having sex. The mother is going up and down on the father and when she sees her daughter looking at them she immediately stops. “What are you doing, Mommy?” The mother, too embarassed to tell her little girl about sex, makes up an answer. “Well, sweetie, sometimes daddy’s tummy gets too big so I have to jump up and down on it to flatten it out.”
The little girl looks at mom and says, “Well, mommy you're really wasting your time.” The mother is confused so she asks, “Why do you say that sweetheart?”
The little girl answers, “Because mommy, when you leave for work in the morning, the lady next door comes over and blows it back up.”