Responses
I think she just felt bad for her because she knew what happened to Maxi’s mom, I don’t think it was a sisterly thing more like how you can’t bear to watch a person hurt themselves in front of you. The sister’s personality was shaped by their father, she chose to be cold to survive and wished Maxi did the same.

Probably a controversial opinion, but I think her sister doesn’t really have bad intentions for Maxi. Or maybe I am misinterpreting this chapter, but it looks more like she is trying to wake her up. No?