I just watched this movie again the other day, thanks to this thread. The reason the aunt turned Matt against his pa was superstition. They pass over it kind of quick, when Matt’s uncle is drunk and speaking his mind at the table he states why. The aunt saw Matt’s mother die and one that sees death will be the next one to die, unless the one that caused the death dies first, or something real close to that. So it seems that the aunt was motivated by fear that she was going to die next. Each time I watch this movie I seem to find subtler story lines than I noticed the time before. This move is moving up my favorites list…