Curious about this myself! Hopefully more context is added, I don't doubt things use to be good between them, but who's to say that despite how OVERPOWERED her abilities are. She's not immune to mental type powers!
I don't think we ever were told about her mother's powers! Only "redemption" I can see is if her mother used her powers to make her see "what she wanted to see" and twisted her personality cause she had refused to "play ball" and seeing her powers! It's MUCH too tempting to leave someone like that out in the wind, even if she didn't. MC might have seen his stepmother do something and while she used her the "kill him as an adult" do to the fact she knows she is STILL heavily suspected to have had foul play in his dad's death.
Of course the sister is involved as it's weird she's onboard with her mother wanting to kill him secretly, but the dream shows something different, especially that outburst at the end of it! God I wish updates would come sooner! It just adds more puzzles and questions. But yeah nothing short of BRAINWASHED into it would even ALLOW the sister a chance at redemption after everything so far. Hope if the writer DOES try, he at least is smart about it, and even then it would still be a cope out since NOW we have a WHOLE different personality to work with (like TWIST villains such as Hans from Frozen and Bellwether from Zootopia, the issue with the twist when it comes out of no where is now we HAVE to readjust to the fact everything we knew about them isn't true anymore and doing it so late makes it ANNOYING cause the NEW personality doesn't have much time to establish itself (unless the "Dreams/Flashbacks paint a BIGGER picture! Something tells me if the stepmom has some type of mind power, it could be the MAJOR reason she wants him dead, likely cause as it gets closer and closer to the date, the as a sadistic monster, you killed them horribly and your getting MOCKED by the one who did it for DEFIANCE! As said, her powers are TOO OP to just get rid of her if she's against the mother. I don't know, all of it is just Theories for now! GOD I wish chill libdndox
