I have 3 hens, all most 2 years age. I got another hen same age. I have divided both my coop and run for the new hen. They all can see each other inside and outside. How long should I keep this set up? What are the signs to put her with the others? And what are the signs that once together it’s not going well, like little fights, or big fights? . It’s cold and the single girl has no one to snuggle with at night.