31 for 21: My teenager in a preschooler body

Today, Tommy didn't want to hang out with us. So he went upstair, shot the door of his room and lay down in his bed with his buddy Elmo. This made me think how it will be when he is a teenager. We are so attached to him that it will hurt us seeing Tommy preferring chatting and spending more time with his friend than with us. But at the same time, this is what we look for.