Over and over, the boy tossed the ball up, smacked it with the bat, and then scrambled to catch the ball before it hit the ground. It seemed like a tedious and painfully lonely sport, this game where the batter, pitcher and outfielder are all the same person. When I asked my friend if we should invite him over, she assured me that our boys were too young to interest him. “But he’s all alone,” I lamented. “He’s used to it,” she replied. “He’s an only child.”