I have eleven 12 week old birds (5 hens 6 roosters) who are currently my flock. Ive hand raised them from 1 day old and they are my first chickens. Ive also ordered six 18 week old pullets from our local co-op (hubby couldnt wait for eggs!) Whom are coming in a few days. I only now discovered that it is recommended to separate new hens from an existing flock. Is this something that is dire? Or would my hens get along where my other flock is so young? 5 of my roosters will be either going to new homes in the coming weeks if I can find them or will be culled.