A little boy came home from grade school one day and saw his mommy drying herself off after taking a bath.
The little boy, curious, asked his mother what that was, pointing his finger at her vagina. The mother, caught off guard, and without thinking, blurted out, "Ah, er, it's my sponge, son."
So a couple of weeks pass and Mom decided to shave her private parts to impress her husband. One day, the little boy came home from school, and saw his mother drying off from a bath again.
Curious again, he asked his mother what happened to her sponge. The mother, embarrassed and surprised, blurted out, "Er, ah, I lost it."
The boy, positively gleeful now, said, "No you didn't mommy, the neighbor lady has it, and daddy's washing his face with it."