Mayhem and Monsters by Kathleen Collier

Answering a summons from his aunt, Derek reluctantly returns to his hometown to confront the monster who made his youth a living nightmare. Unfortunately, dementia prevents Derek from having closure when Doug doesn't recognise him. That night, Doug is found dead by unnatural means and all eyes swing to Derek's aunt. Derek is convinced his aunt didn't kill her husband but is also convinced she knows who did and she isn't talking. Now the pressure is on to find the killer so they can bury Doug. The sooner he can get the hell out of this town of poisoned memories and back to the city before his wife goes into labour, the better. It's proving easier said than done though...