Becca was six years old when her sister killed herself, she left no note and no answers. Ten years later and Summer has become a dark spot on Becca's life and nothing more. A sister she hardly remembers whose existence is brought up only on birthdays and special occasions, She's an awkward conversation and a sympathetic look. Until Becca writes Summer a letter and everything changes when she gets a reply. Summer has two rules: Don't tell Mum and Dad and don't ask why. But Becca needs answers and she's starting to realise that maybe there was more to Summer's death than anyone ever realised.