October Novel Prep Challenge

So now that i finally have a complete outline I've run into a problem. I have a 3 main characters... well, more like 1 good, 1 bad and 1 that is good but not quite a main character. But When writing my outline, I added another minor character because, at least at this stage, it doesn't seem like the action I needed to have someone complete would really work out if it was one of the MCs doing it. But now I have this person hanging out in my story and I don't know yet what to do with her. Does this issue get resolved with a more detailed outline or with really delving into her story? Should I just let her hang out until I know if I need her, or should I rework the minor conflict and write her out?

Ah, planning, you really are making my life easier in November.

{e;cat}