Several years ago, my sister and I watched my 2-year-old nephew’s behavior change dramatically. He started wetting the bed, throwing temper tantrums and getting frustrated so quickly. In any other child, it might have been normal “terrible twos,” but in him we knew something was definitely wrong. At the time, my sister and her husband were getting divorced. Ultimately, we found out that my nephew thought it was his fault, thus the acting out. This was my first exposure to the impact of...