This is Tiffany (we thought) and we have a layer (they are all about 6 months old) but we don't know who is laying. Tiffany took over as head hen we got rid of our roo. She's obviously in charge but when she picks a fight the others will challenge her. She's frequently mean to the other 5 ladies. They all perch up top in a bar at night but this one stays on the lowest perch alone. Recently she has been mounting the two older hens, as much as three times in the hour I was outside with them. She is bigger then the other.... Please help!