"Grandma Nancy," my son informed me tonight, as he has done several times before, "does a much better job scratching my back." "Yes, I know, honey," I sighed, as I tried to slow down the tempo of said back scratching. "It's because she's much calmer than me." Since Lawrence was a toddler, my stepmother has, on demand, indulged him with a few minutes of back-scratching whenever she sees him, during which he becomes absolutely boneless and quiet. She is somehow able to transmit her calm and sense...