Hi, my gelding some days is just a s.o.b. To my little mare who is 1 1/2 years old. I know we all have our off days but sometimes his has alot of off days, just today he nipped her hard enough in the front leg to cause her to bleed and took a pretty good chunck out of her. And sometimes he is just a sweetheart. Why???? Is there something I am missing.