We have two tiny (bantams?) hens and a small bantam rooster all a year old. We just got 6 chicks and they are 3 weeks old. We are building a new coop for them all and if warm enough just going to put them all out in the new home at same time in two weeks. Will that work as the confusion sets in and the newbies will be almost same size as older ones? One of my year old hens is really a snob and the other one is really sweet.
Introduce them with a temporary see-no-touch set up. Let them get to know each other thru the fence. You might put the sweet one in with the youngsters first.