I ’ve always found pie to be intimidating. Not eating it, of course; I couldn’t be more at home slicing a slightly larger piece for myself than, say, you, and tucking into it with whatever whipped cream or ice cream or any other cream that might be handy. It’s pie making that’s always seemed like a deliciously remote art form, something swaddled in secrecy and passed from the flour-dusted hands of one generation to the next. Sarah Weeks’ Pie, a sweet mystery for middle readers about love, loss and friendship, takes the titular dessert that has always served as a subject of personal fear and fascination and turns it into a metaphor for our connection to others while somehow managing to demythologize actual pie…