The dead fathers club / Matt Haig.

Enhanced descriptions from Syndetics:

A ghost story with a twist—a suspenseful and poignantly funny update of the Hamletstory Eleven-year-old Philip Noble has a big problem: His dad, who was killed in a car accident, appears as a bloodstained ghost at his own funeral and introduces Philip to the Dead Fathers Club. The club, whose members were all murdered, gathers outside the Castle and Falcon, the local pub that Philip’s family owns and lives above. Philip’s father tells him that Uncle Alan killed him and he must avenge his death. When Philip realizes that Uncle Alan has designs on his mom and the family pub, Philip decides that something must be done. But it’s a much bigger job than he anticipated, especially when he is caught up by the usual distractions of childhood—a pretty girl, wayward friends, school bullies, and his own self-doubt. The Dead Fathers Clubis a riveting, imaginative, and quirky update of Shakespeare’s great tragedy that will establish Matt Haig as a young writer of great talent and imagination.