Also having two waterers and feeders separated can be helpful while they figure it out. When I added 2 younger pullets to my flock of 4 hens last year, the younger ones hung out in the coop and watched the others and periodically would venture out (one was braver than the other) , get chased and then retreat. Having food and water in the coop allowed them to eat. Roosting time all were ok, a few pecks here and there and all would settle in. It took about 3 weeks but eventually they all figured out where they fit in and got along.Good luck!