Another of the wives, yes. I think that Raven is being planned as #2 so she's from the very start, almost. Raven is an admirer of strong women. Especially ones that look younger than they really are, like her. You're right, they could get along splendidly or not at all. I'm going to take a page from Kass' book and say both would be acceptable. Perhaps they didn't get along when they first met (Raven isn't looking to connect with anyone and then watch them die) but when she sees how strong Cee is, she decides to stop being so unfeeling and rude toward her.
How cliche would it be for all the wives to dislike each other as well? Girls have to stick together.