AfterMath by Emily Barth Isler

This book is a gift to the culture. --Amy Schumer, writer, actor, and activist

After her brother's death from a congenital heart defect, twelve-year-old Lucy is not prepared to be the new kid at school--especially in a grade full of survivors of a shooting that happened four years ago. Without the shared past that both unites and divides her classmates, Lucy feels isolated and unable to share her family's own loss, which is profoundly different from the trauma of her peers.

Lucy clings to her love of math, which provides the absolute answers she craves. But through budding friendships and an after-school mime class, Lucy discovers that while grief can take many shapes and sadness may feel infinite, love is just as powerful.