I have two groups of hens: The older group of 4 (3 Rhode Island Reds and 1 Buff Orpington) -- these hens are fourteen months old now, and have been raised together as a group since they were two days old The younger group of 6 (2 Buff Orpingtons, 2 Barred Rocks and 2 Easter Eggers) -- these little girls will be about 17 or 18 weeks old when I will begin to merge the two groups. The older group lives in a 13 foot by 7 1/2 foot chicken coop that currently has two discrete nests for laying, plenty of feed and water, a nice fan to keep them cool in the summer and a heater to keep them warm in the winter. It is plenty big enough to take in the little babies when the little ones are old enough to handle the big girl layer feed. We have plenty of room in their nesting area to put as many as two more nests, and will add these nests before the two groups are merged. The younger group currently lives in a 8 foot by 30 inch chicken tractor that I move frequently to give them fresh grass to feed on. They have everything they need, but that tractor does seem to shrink in size as the little peepers grow bigger. This group has also grown up with each other. Both groups get three to four afternoons a week (weather permitting) to free range out in the open yard, but at this time, I have not allowed the two groups to free range together. Both groups live pretty harmoniously with others in their own group. I don't see any of that hen pecking that other chicken families seem to experience. I will need to merge the two groups so that they can live together in the big chicken coop (the one that the older girls live in right now). But how do I do that, without causing friction and fighting? I am willing to merge them gradually and be patient with them, but what I really do not want is for there to be fighting or violence among the hens. What is the best way to merge these two groups?