Revolver, Paperback/Marcus Sedgwick

Set in 1910, a cabin north of the Arctic Circle where 15 year old Sig Amdersson is alone, except for the corpse of his father, who died after falling through the ice. When a man claiming to have unfinished business with his father arrives, Sig's thoughts are drawn to a hidden box containing his father's revolver. Sigs choice is pulled into focus. Should he use the gun, or not?