I have a small coop large enough for 4 chickens. I had 2 and 1 was getting old and stoped laying. I added 2 new "ready to lay" hens and got rid of the old one. My problem is the 1 original bird is beating up on the 2 new ones to the point that she won't even let them off the roost to eat. I have been locking her out of the coop a couple hours a day to let them eat and drink. Is there any thing i can do to stop her from beating on them.