Bantam is a distinct possibility. It's happened before. If peep is eating and behaving normally then go for bantam. Or was this peep a filler chick? And now that I think about it, bantam is highly likely since bantams can not be sexed as day olds.
I'm not very good at id'ing any breed I didn't raise so I'm not even going to try to guess.
The 1st picture is a rooster,the comb and wattles are too red for 9 weeks old.The other ones need a better picture of their combs and wattles.Please enlighten me! I was guaranteed a 95% sexing accuracy!! I'm not going to be happy! One I can understand, anymore please no!
Thank you! The small one does eat, drink and forage well. She hangs tough with the others and participates in the chest bumps and is cute because she has to do a jump to reach the others, lol.They all look like rir, I would say the smaller one is a late bloomer or a failure to thrive. All are pullets with the possible exception of the one sitting alone on the perch. In my experience rir are bred to be quick maturing and my pullets all got semi large combs by 10 weeks that were already getting color. The only roosters I've gotten had very large red combs at 5 weeks and were very clear roosters. I believe all of yours are hens but would watch the one that I mentioned above.