I had 2 cockerels in with 2 pullets and 7 hens. By age 3 or 4 months, there was a lot of havoc, the boys chasing and fighting. The higher ranking one always in pursuit of the other, who crashed into everyone, into fences trying to get away. The lower ranking one was often trying to grab the pullets when he thought big brother wasn't looking. The older hens tried to discipline them but to no avail. They were all stressed out much of the time. I sold little brother at the poultry swap, and ah, peace again. Big guy is always polite to the girls, and everyone is happy.