I believe it is the same age as the ones right next to it. It was about half the size of all the others when I bought it. It was featherd out the same in the wings but just smaller.
Then yes it looks like a bantam. I have one exactly like it--well, not EXACTLY...it's blue. *laugh* S/he is a tiny little thing, too. I have no idea what kind of bantam it is though. Hopefully someone will solve the mystery for us!