I can't remember who had posted about their difficult child chewing on the clothing, but something occurred to me today on the subject. As I mentioned on the other thread, when I was adolescent, I do remember chewing on my shirts for a while. I also chew gum daily now. But what occurred to me today is that to this day, I also grind my teeth. I wear a bite guard at night to prevent further damage to them, because that's when I do it the most. But, I grind them during the day, too. Chewing gum seems to make me bite down less hard. But it might be a good idea to have your child's dentist look at their teeth for signs of grinding. It's terrible for the teeth, hard on the jaw, and makes it difficult to relax. Perhaps a bite guard could help.