I recently got 4 new chicks and they are now 4 weeks old. I have 2 australorps, an Easter egger and amethyst. The problem I have is one australorp is very aggressive towards the other 3 to the point the run from her. She is also larger than the other 3. I constantly hear them screaming as she pecks at them, pulls their feathers. So, what should I do? I don’t think this is a cockerel, but I can’t tel. I have tried to separate her out, but it did not help.