Hi, I am first time chick Mommy. I have ten females of assorted sizes and breeds. They are all suppossed to be large breeds, but two are smaller and two are larger then the average size. They hatched 5/17. My concern is they fight. The all seem to be particpating. It squares off to two chest butting and flapping. They also love to dive bomb each other.No one is being injured. Is this normal? I know they are overcrowded in the brooder, and we are moving to the coop this weekend.