She's a Bantam, right? Does she have a regular comb or a rosecomb? Also, are her earlobes red or white? There are a few different things she could be. If she has white earlobes and a regular comb, then she may be a Black Dutch (I have a rooster and a pullet right now, but they are solid black...
This one's looking like a Rhode Island Red Bantam, but can't be sure until he's finished feathering out. Can you post a picture of the solid black one? I think I can help.