I heard one of my girls "Hawk" purr for the first time the other day..... she melted my heart! I was walking from the "back 9" of my yard carrying her and she started to purr when she placed her head on my chest......
I find that one of my girls is a complainer more so than I originally thought. She 'screams' when I feed them and do not let her free range. (they share a yard with dogs too and I have to make sure they don't meet by accident) She screams when the food isn't to her standards ( I never knew...