When Santa and the Grinch Visit: Choosing Magic and Wonder   There is a quiet, tender transition that happens somewhere around middle childhood, the moment when believing in Santa begins to soften, blur, and eventually give way to knowing. It is a transition not only for children, but for parents too. And like so many transitions, it doesn’t happen all at once. My son is ten now. Last year, I think he figured it out, but only after Christmas had passed. Not in a dramatic, con