That night I experienced one of those sudden, unpleasant shifts of perception that occur to parents, when you notice a difference in your child that's been coming over a long time, and you're faced with it, and at the same time you're groping back to touch the child they were a minute ago, while a somehow unaccountable, unpredictable person is watching you, waiting for you to catch up with them, contemptuous because you haven't.