People fear death (apparently just a tiny bit less than public speaking). We don't know how to talk about it, especially to children, and we're afraid to bring it up for fear of making people sadder.
Yet children, especially, have questions, and this incredibly gentle and surprisingly light story is full of both comfort and vividly imagined "answers." The first one gives the book its title: A boy hears the voice of his sister calling him one day, a sister he's never met because she died before he was born. The sister in the faded photograph on the wall. So that night he asks his mother what death is like and she tells him, "It's like dreaming, only bigger."
That's lovely, but he still has questions, which it turns out his sister can answer! On a dreamy, carefree adventure they ride their bikes together, (not always on the ground), visiting places that were special to her when she was alive. And she talks to him in the older sister, teasing, straightforward, loving way that is exactly what he needs. (It turns out that death is not the only thing that can be Bigger Than a Dream.)
Much, much more than bibliotherapy, this is a work of art that speaks with honesty and tenderness about one of life's great mysteries