If she is a child she is a dangerous one. No I don't see her as a child, but rather as an insane person who refuses to take her medication (healing) confusing accepting help controlling her disease with letting others control her. The main consequence is that she lets herself be controlled by her insanity. She is more a tragic monster than a simple "bad" against which the heroes are pitted to get them to shine. Winnie is too deep a character to be just simply wicked.