So this was the bite of 87 at the sister location.... which was running with fredbear and springtrap. While the other location in the second game had freddy and the gang. On the sixth night you close down that location cause of this accident. So this happens 11-13-1987, so how do we explain the animatronics acting so strangely in fnaf2? Because the murders happened before that, the original models where the first 5 which we read what happens in fnaf 1. Wait but golden bonnie and freddy when are they created? Cause they where the brand new version 2 models that where released simultaneously at this location. But why does the kid have the dolls in 4 you ask, cause of his brother originally going to freddy fazbears pizza thats why he has freddys head. The boy is scared of the new characters cause his brother told him what happened at fazbears to scare him. We now know about the bite we know the timeline is fnaf4 & 2 then fnaf ending with fnaf's 3. But then who are we in fnaf's you ask? You are purple guy, trying to get back to where you murdered. But the animatronics try and get you killing the original manager in the processes(the original owner of Fazbear's Phone guy) So you do what must be done, destroying each one. But we know how that turns out.... and the ending is the 5 original murdered kids passing on with this kid in the coma. His original friends those dolls, those souls the only things that made him happy. So the final chapter dlc should be either them helping getting this kid out of his coma/ passing on or giving purple guy a motive to do the original killing. This is the timeline, and story of Five Nights At Freddy's

Or at least my interpretation of it :D