One small chick...did we get a different breed?

[AKoz15]

We got all 4 of these chicks at TSC at the same time, same bin of sexed Rhode Island Reds. They are around 6 weeks. Two questions:
1. Did we get one of a different breed possibly? The little one in the first pic has always been soooo small, although she eats and drinks fine, and is almost fully feathered like the others.
2. Do you see any roos or can i trust we got 4 hens?

 

[Party_Chicken]

They are all hens. She may just be a runt. I know they also sell bantam RIRs so she may be that.

 

[RoostersAreAwesome]

Bantam RIRs are much smaller, though she could be a different large fowl breed.

 

[BastyPutt]

I think she is just small. Every year we get a small one or two. If it was reversed, and you had one noticeably larger, I'd say you'd have a cockerel - but although early, they do appear to be pullets