I have a flock of 6 chickens and I have discovered that one of my chickens is actually a rooster (they are about 15-16 weeks old). I am going to be giving the rooster to a friend who has lots of land and the chickens free-range. In return he is giving me a hen. What is the best way to introduce this hen to my existing flock? I was hoping that I could do a clean swap but my logical brain is telling me, along with research, that is not a good idea at all.