From what I'm hearing you say, 2 of the older 5 are being bullies, the other 3 older chicks are ok with the youngsters? My recommendation is to separate the 2 bullies from each other. When I had to integrate chicks, I started by putting an older chick into the pen with the smaller chicks, then adding the older ones one at a time until they were all in the new space... it seemed to work better to add the older chicks into the younger chicks space for integration, as the younger ones were already established in their own space, and the older ones were entering a new environment. I think the 2 bullies are feeding off each other. Just a suggestion, you might take one of the bullies away for a week, and put her with the 3 younger ones. Loneliness might make her bond with the newbies, then you could add these 4 back to the other group. Eventually, they will sort it out. I think as a chicken owner, it's harder for us to watch than it is for the youngsters to experience.
