You look behind the gravestone...
Wow!                                                                                        
It's a book about how to survive this house!
It says it was written by Jake Samson.
It was written in blood!
On the first page it says:
I'm writing this to warn others about this house.
I've been in here for almost a year.
I know how to get to the treasure but I have no use for it.
I would give anything to see my family one last time.
My friend came in here looking for me and was killed.
I'm getting faint. i have to stop writing.
                                      !
A significant portion of the book is ripped out, with no other entries remaining.
You resolve to take the book with you, in case other pages are nearby, and try to find a way out of this graveyard.