I think the continuity between all of the books share the same universe, I would belive the time line would start from the 12 screams of cristmas prologue and then going into welcome to dead house. Then the Night of the living dummy 1. After the events from the first Night of the living dummy, Slappy is bought from a local pawn shop, we know this is the same dummy because Slappy is shown to have a moldy sandwich inside his head. Then id really dont know were the story goes
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