What begins as just a normal Tuesday becomes a day that will shatter sixteen-year-old Kai's life forever. All it takes is a letter, tucked into a pile of their family's mail. It's from Kai's older sister, Jen, who lives nearby. And it begins, "If you are reading this, I am already gone." Jen has committed suicide. Dazed, Kai helps to plan Jen's funeral and tries to cope with their devastated parents, all the while searching for answers. How could Jen do this, and why? Kai is heartbroken and furious, and soon she's caught in a vicious downward spiral, self-medicating and lashing out at the people she loves. That's when her parents shock her: they're sending her to the Tree House, a summer camp for grieving teens. Kai is not a happy camper at first. But when she meets other kids who are grappling with loss, she begins to share her feelings, find a way forward, even laugh ... and fall in love.