Queen of Everything
Okay, some possibilities I see. I'm going with the idea that Nia is from the same village here, and that...consequently...that village is now gone, and the person(s) responsible for cursing Kat's dad and therefore her are now dead. But as we all know, curses linger.
1) Though the curse was at the behest of the Chief, it was actually laid down by someone else; a practitioner of the magic arts. Inka had been training to succeed this person, and once she left, a new apprentice was found. This was Nia. She would have been quite young still when Inka was returned, dead, and the curse was cast...but would still remember something like that.
2) Inka was the Chief's daughter, but not his ONLY offspring. He had a son, or another daughter, and Nia is their daughter...she's therefore the Chief's grand-daughter...much as Kat herself is. This tie between them isn't known by either of course, though it's possible they could put the pieces together if they open up to one another.
Either way, as Nia is the only surviving member of the tribe and/or family of the one that cursed Kat's line, there may be a way to end it through her somehow... BUT HOW?
Edit - Come to think of it, these two possibilities aren't mutually exclusive. Why agonize over a decision when we can use it ALL?
What do you think?
Nia's all human. Which would mean that th...oh. Was Inka elf? Thaaaaaat would alter how things could happen. Though it COULD still work, if the Chief had more than one wife, perhaps. But it might be overcomplicating things. We can just go with option 1 in that case and say there's no blood connection.
When I read your initial post up there I thought the same thing - why not use it all! I think it works very well and more importantly, I LOVE it! Katerina is human and I envisioned her mother - while exotic because of the voodoo thing - as human also. One of Kat's defining bonds is finding a way to break the curse asap so I think it would be great played out as she's trying all these different things (she's been working on it, I think already 2 years, while before her father died he had been doing it for years also) to eventually have had help next to her all along. Great stuff.