"Mommy, where do babies come from?"
The mother thinks for a few seconds and says, "Well dear, Mommy and Daddy fall in love and get married. One night they go into their bedroom, they kiss and hug and have sex."
The daughter looks puzzled so the mother continues, "That means the daddy puts his penis in the mommy's vagina. That's how you get a baby, honey." The child seems to comprehend.
"Oh, I see, but the other night when I came into your room you had daddy's penis in your mouth. What do you get when you do that?"
"Jewelry, my dear. Jewelry."