I know this may be a bit stereotypical, but maybe due to a poor action that one of her ancestors did, her whole family is getting affected with different types of cursed? For example, your gal might have to deal with recurring nightmares and her sister could be extremely forgetful. It doesn't have to be a huge, pressing issue; it could be as simple as my suggestions! Also, it could be up to you whether your protagonist(s) decide to do something about it or not!
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I've really been struggling to find a name that I actually like for this character; I've been struggling with this for about a year now. If this helps, I'd love something masculine and gender neutral! Feel free to search for unusual names as well!