Several years ago, we were having a family gathering at a rather nice restreraunt. My grand-neice, Amy age 4, asked her mother if sex hurt. The entire resteraunt went silent and all eyes turned towards our table.
Her mom answered "No Amy, why would you ask that?"
Amy responded "Then why do you scream when you and Daddy are in the bedroom?"
The entire resteraunt erupted into laughter!