Responses
the sister doesn't have that power of controlling other peoples hearts though. that power is from Miyo's mother's side. No one in the family would have that power except Miyo.
Oooh, I had forgotten that was an ability of Miyo's mother's family. That being said, we know that the father's side of the family also has special ability users, and Kaya is known to have at least some sort of power, so I still think it's a possibility that she could have something to do with everyone's attitude towards Miyo.
Doesn't Miyo's family have the power to influence other people's hearts? Is it possible that not everyone at Miyo's house is an inherently bad person, but rather have had their hearts influenced by the sister for so long that they've become bad people? Because honestly, I just can't see why some grandpa, who isn't even related to Miyo, would have a hate boner so hard that he's willing to burn his own house down. Especially since he should want to keep the sister married to his son, so that she passes her powers down to his grandchildren, instead of letting some other family get those powers instead.