Shannon has been the backdrop of my life since the moment I was born.Summer Stetson lives inside a shrine to her dead sister. Eclipsed by Shannon's greatness, Summer feels like she's a constant disappointment to her controlling, Type A momzilla and her all-too-quiet dad. Her best friend Gibson believes Summer's C average has more to do with rebelliousness than smarts, but she knows she can never measure up-academically or otherwise.On her birthday, Summer receives a secret gift from her aunt: Shannon's diary. Suddenly, the one-dimensional vision of her sister becomes all too solid. Is this love-struck, mom-bashing badass the same Shannon everyone raves about? Determined to understand her troubled sister, Summer dives headfirst down a dark rabbit hole and unearths painful family secrets. Each revelation brings Summer closer to the mysterious and liberating truth about her family-and herself.