My dd's pet hen disappeared in the fall. We suspect a hawk got her. Naturally, dd wants to get a replacement in the spring, and I'm happy to do so. However, there isn't really space in our chicken tractor to add more than 1 more bird. In the past, I have added new hens 2 at a time. I'm a bit concerned that if I add 1 new one on its own that it will have a harder time with all 5 hens pecking it. Can I safely add just 1?