⠀ question about small chickens

[AmyLittle]

I am not sure where to post this question but I'm hopeing I can get some info here. I have 12 smallish chickens they are about a year old. I got them last year when my brothers four chickens two roosters and two hens had them. These chickens were small and all four looked different. Some with feathers on they're feet. My question is that the babies haven't even grown as big as they're parents. My roosters are about the size of they're mother's. They seem healthy otherwise. I will try to get pictures of some of them but without seeing the parents I doubt it would help.