So Laura Lee or Melani's mum? Could be.
Or could be at a greater remove - an aunt or grandparent, someone who has been deceased for a while, who hasn't made the news. I'm assuming none of them were actually called Amy, or LE would have found her when they worked up a family tree. Not like it's hard with active LDS, especially a hyper religious one like Lori, going to the temple daily. She'd have all her ordinances done for direct relations, and they'd all be in Family Search. An Amy would have stuck out.
MOO