Not sure if this is in the right place, but two of my hens (Leghorn and Australorp) have been mounting, and squishing my little ISA Brown. I havent seen it but my parents have.. apparently Ginger (ISA) ran near the other do, stopped and did that funny chicken squat, then Eve (Leghorn) jumped on top of her and squatted, and Lily (Australorp) was about to jump on top of them. WHY??? What could possess them to do that?? And how likely are they to hurt/squish her??