The Death of Bees by Lisa O’Donnell

Marnie and her little sister Nelly have always been different. Marnie leads a life of smoking, drinking and drugs; Nelly enjoys playing the violin, eating cornflakes with Coke and reading Harry Potter. But on Christmas Eve, the sisters have to join forces and put their differences aside. And when Lennie, the old guy next door, starts to get suspicious, it’s only a matter of time before their terrible secret is discovered.