Funny Dirty Joke

I remember a few years ago when my little girl was only 8 years old, she came up to me and asked, "Daddy, what is sex?" I was somewhat surprised that she would ask such a question. But, I figured if she's old enough to ask the question, then surely she's old enough for a straight answer. So, I proceeded to tell her all about the "birds and the bees."
After the explanation, my daughter was a little pale and wide-eyed in disbelief. "By the way, dear, why do you ask?" I then asked her.
She then replied, "Mommy told me to tell you that dinner would be ready in just a couple of secs."