It's hard to keep close a person everyone keeps telling you is gone. It's been sixty-five painful days since the death of Juniper's big sister, Camilla. On her first day back at school, bracing herself for the stares and whispers, Juniper borrows Camie's handbag for luck - and discovers an unsent break-up letter inside. It's mysteriously addressed to 'You' and dated July 4th - the day of Camie's accident. Desperate to learn the identity of Camie's secret love, Juniper starts to investigate. But then she loses something herself. A card from her daily ritual, The Happiness Index: little notecards on which she rates the day. The Index has been holding Juniper together since Camie's death - but without this card, there's a hole. And this particular card contains Juniper's own secret: a memory that she can't let anyone else find out.