Hey Guys, I have rescued a dutch bantam hen from my grandma that her other chickens just couldn't get along with. I have 4 original hens, 3 of which are doing just fine with her. My fourth and smallest original is being a "bully" and won't stop attacking her. I have 1 coop, which is in a fenced 15x12 foot pen back by the garden. Do i need to build a second smaller coop to isolate the bully? Thanks! P.S. I don't know if this is important, but my four original hens are different breeds than the dutch bantam rescue. 1 new hampshire red( ring leader), and 3 black australorps.