EE Chick not growing

[GoodStuffMaynard]

I have 6 Easter Egger chicks that are all the same age. Almost 4 weeks old.
One is just not growing. It's about 1/2 the size of the others and only has a tiny bit of feathers on the tip of the wings. And the feathers it does have look weird. Should I be worried about this chick? Is there anything I can do for it?

 

[JamieOnion]

Well I think you are looking at a pullet and 2 roosters. They are a little larger. Only 4 weeks looks about the right size, Those are new feathers you are seeing.