Sleeping Teens

I think I've mentioned before I have teenagers. Thanks to Presidents Day, they don't have school. They are still sleeping. I am hoping that they don't grow in their sleep (is that an old wives tale?), because by now, they'd be 6 feet tall! I seriously don't remember sleeping that much when I was there age. Maybe my parents didn't let me. I don't mind them sleeping in.....I just can't believe they can sleep so long!