How many of the heroic company would recognize the villainess? Not the current point of view character, I realized, or this one, or that one -- and then I wondered if anyone except the heroine herself would. It's a large group, almost unwieldy, but the villainess has been operating off-stage during the novel.
Except, I realized, the heroine's half-sister. Yes, the villainess is the heroine's mother, but she's also the half-sister's stepmother.
Hmmm -- not that it's difficult to have the heroine be the one looking in the right direction. Her sister can gasp when she points the other woman out.