I have two chickens, an ameraucana and a lakenvelder. I recently lost my third hen to fowl pox and heat exhaustion. The other hens miss her and now that the flock is down to only two the girls scream like crazy when the other hen is out of sight. This is especially problematic when the other hen is trying to lay her egg. I think a third hen would be good to keep the non-layer company but it seems new adult birds are difficult to successfully introduce. I realize I need to get a vaccinated hen since my current hens are pox carriers. I do not have room for a lot of hens. Can I add just one? My lakenvelder can be aggressive but she is small. I am considering getting a red sex-link of the same age as my current birds from a local feed store. My ameraucana is very sweet and smart I am less worried about her reaction. Any advice on how to add to a small flock?