The little girl's next question is even more of a challenge,"Daddy, what is it called when a man lies over the top of a woman".
After a lengthy introduction to the birds and the bees, bewildering the girl even more, the father adds,"Where did you come across that"
"Little Johnny over the road does it with his sister", replied the girl.
Father was shocked, but decided to keep quiet.
Next day the little girl comes home from Johny's house and says,"Johnny's dad is coming over to see you later. He says it's called bunk beds"