I currently have a flock of 14 chickens, 7 were mine since babies and 7 I bought as pullets. These two groups integrated beautifully. Since then I've rescued 2 other chickens (a rooster and a hen I believe) and they're now at the size and age where I thought they might integrate. I initially tried about 4 weeks ago, and the older chooks pecked all the tail feathers out of the back of the hen leaving a bloody, yucky mess, so I rescued her again and put her and her friend the roo back in their little apartment. Last night we thought we'd put them down there when it was dark as we'd read online that this means by morning they would all smell alike and everything would be fine. Everything is not fine. They've bullied the same poor bird again and she doesn't look good. As she was only just starting to grow her tail feathers back, there was mainly skin showing and they appear to have attacked her. What can I do to ensure my hen heals? Why won't my chooks integrate? Why do they only attack the hen and not the rooster? I'm feeling really guilty so I've spoilt them rotten since they've been back in their separate enclosure, what else can I do??