Well....after I put straw in the little coop and hooked up a heated bowl, she took those little ones into the big coop again - and stayed this time. It would work perfectly to have all of my chickens in the one coop just in time for winter. BUT - you guys are saying I don't need to worry about them being pecked to death by the other chickens in the morning before I open the door? I'm worried about that because I would never put chicks that little in with the big ones.