For anybody still searching after all this time: the 15th Document for the South Quarter, "Polly's Admirer's letter" is in the room directly above the room where "Little Lucy's Last Letter" is found (where you jump onto the rope from). I think it was on/in the nightstand. My game says 15/15 documents now, so I don't think there is a 16th.

@raiwalks thanks. I haven't even played this game in over 3 years, let alone edited this guide. if you remember where you found it, comment here and that should be good enough for people to figure it out. thanks again :)

Hey, there's another document you don't list. I just don't remember where I got it-- it's "Polly's Admirer's Letter".

I just found it.. it was inside that room I was talking about, but just not in the secret shelves behind the wall.. it was in the other shelves left of the window. I don't know how I missed that the other two times I went there

@dimmu1313 Yeah, actually I'm talking about the numbers in your guide, but it doesn't say how to reach the location or where is it, just the name of the document. Thanks anyway for replying