"Simple, elemental, yet full of heart, the story, remarkably, captures a character who isn't there and makes readers see him just as Leon does." -- Booklist Leon is new in town and doesn't know anyone. That's when he makes friends with Bob. No one else can see Bob, but Leon knows he's there. One day a boy exactly Leon's age moves in next door. Leon would like to meet him, as long as Bob comes along. But suddenly Bob is gone. How...