Harry, wriggling on the bench at snack time, sends a box and a book tumbling to the floor. He peers over the end of the bench at his handiwork. "It's okay," Harry reassures me. "No one will trip over them. We can just step around them." "It's okay," I assure Harry, "we won't have to, because you're going to pick them up now." "Oh. I can do that, too!" Yes, indeed.