Do you mean the purple thing behind her hair? I don't think it is.. but it could be.
I'm pretty sure she's an old woman, because I read previews from sites who have played the first few hours of the game, and they say there was an old woman waiting at the end of the sealed grounds who let you pass into the forest area. That area in the trailer looked like it belonged to the sealed grounds, so I'm guessing this is that old woman.]z
What the old woman does or what her significance is I'm not sure, though