Ah right half sisters I don't know where I got step sisters from :} Well I haven't said her third power yet is why :p What was Elena's other power again, other then the truth and pain one? 

Hmm I like the idea of their fathers being the one to set them on their path when they went opposite ways.

Well I guess that would depend on how well they got a long before leaving. I know that Grace is a little bossy but for the most part she is really the violent "rule with an iron fist" type unless she has a reason to believe she has to be. 

Yeah I agree it will be a lot more fun if it were a surprise.