What is the difference between girls aged 8, 18, 28, 38 and 48, 58 and 68?
At 8, you take her to bed and tell her a story.
At 18, you tell her a story and take her to bed.
At 28, you no longer need to tell her a story to take her to bed.
At 38, she tells you a story and takes you to bed.
At...