I don’t see them being related (as in blood relations), but I do think there is a lot more to their history than we have seen up to now. Hopefully we will get that filled out in future episodes. In “Skin Deep,” Rumpel says, “You’ll never be more powerful than me,” which indicates to me that she has been working on deposing him for a long time. Does she know where his power comes from? Does she know how he got it? Would she consider taking it the same way, and getting herself cursed and ugly? (I highly doubt that one!) It seems clear that Rumpel is the one who has the power, and EQ tries to make him wield it to serve her purposes. So far Rumpel/Gold has done that, but I think there is a limit. I expect we’ll see more of them pushing each other in upcoming episodes, now that they are out in the open that they both know their true identities.