So we have 8 chicks. They are all almost 4 weeks old and growing fast as chicks do. But we have one chick, a Cuckoo Maran, that is just small. She seems to be growing as well, but not as fast as the others. She just kind of hangs back when the others run to the food in the morning, then eats when they are done. She isn't as active as the others, but we still find her sitting calmly on a roost or on top of the feeder, etc...every now and then.
I am hoping she's just a runt and isn't having any problems. Her fluff/feathers look just like the others, only smaller. We've checked her for any visual issues and don't see anything.