User blog comment:Zathronas/Analysis by an author: Volume 2 episode 6: Burning the Candle/@comment-10380701-20140905013658/@comment-10380701-20140905020538

It's certainly probable right now. But as of now, I'm leaving open the possibility that Cinder is not related to Team RWBY by blood.

The cliche I hate the most is "X is related to the main character after all!", because there's quite a lot of potential to be done even if the main antagonist is not related to the main characters.