My three-year old EE Flo has been brutalized by Linda and Sylvia, two two-year old SS, for this past week or two, steadily getting so bad that Flo is now so terrified of the two that when they corner her, she goes into a submissive crouch, like she would for a rooster mating her. To do that for another hen, as I understand it, signifies the ultimate in bullying and being victimized. High strung to begin with, Flo had begun to dart around, clucking nervously. She has stopped laying because she's a nervous wreck. So day before yesterday, I began to keep Linda and Sylvia segregated with the rooster Penrod.That night I let them back in with the other girls to roost, but Flo was so terrified, she slept in a nesting box. So as of last night, the terrible twosome bunked with Penrod. Flo was calm this morning for the first time in ages. Can someone tell me how long I should keep these two trouble-makers segregated in order to see any lasting change in eveyone's behavior?