First off I would like to say I'm new to raising chickens. This site has been a big help. This is my first post so hopefully you guys can help. We have an assortment of 39 chicks they are roughly 5 weeks old. 10 of which are black australorps. They were all bought at the same time. The pictures are of the one we deemed Chicken Little. It hasn't grown a whole lot. As you can see compared to the other chicks. Is it a runt? Is there another explanation? Thank you in advance. Any help would be appreciated.