I'm Sorry is full of quirky details and remembered snippets of conversation, most of it revealing in its everyday ordinariness. It turns out you can learn an awful lot about a person by what her dad chooses to confide in her, or what her brothers tease her about. I'm Sorry might sound like a sideways swipe at a memoir, but nothing could be further from the truth — it manages to be nostalgic, sad, and pee-in-your-pants funny. A–