I have 2 ISA Browns, and 2 Black Australops all around 17 weeks. Theve been separated from my three older chickens but inside the coop since they were about 8 weeks. The problem is that the chicks are scared of my 2 hens (Black sex link and a Bard Plymouth Rock) and my roo (Ameraucana) and the chicks will not come out of the coop and into the run. My 2 hens and roo are around 39 weeks. When the chicks try to go out into the run, they will be chased down and pecked by all three older chickens. This has been happening to the chicks since we stopped separating inside the coop at 12 weeks old. They all sleep in the coop together peacefully but the 4 chicks still do not roost.