One of the pivotal questions in life is this one: "What does it mean to grow up?" How do you know when someone is mature? When is someone real?

Most of the time it doesn't have anything to do with age. I've known some 20-year-old girls who live like they're 75-year-old old maids. And occasionally friends will even ask me what I'm going to do when I grow up.

What does it mean to grow old? When buying a ticket to a movie theatre, you're an adult when you reach 13 years of age. The state says you're old enough to drive when you are (depending on your state law) 15 or 16. They say you're old enough to drink alcoholic beverages when you're 21 and to vote when you're 18.

Margery Williams gave a classic answer in a book, The Velveteen Rabbit. It is the story of a little boy's nursery. The nursery wa…