We live in the city and have three plymouth rocks--they're about 9 months old and have been laying really well for a while now. We aren't always home but when I am home in the AM I can sometimes hear a ruckus coming from the henhouse and when I investigate 100% of the time it's our head hen, pestering whoever else is trying to lay. Of course they're all laying in the same box and have to take turns. In the past I was annoyed for the other hens but figured they need to work things out because I'm not always around to referee anyway. But this morning there was blood! I noticed one of my girls looked weird in her wattle and combs--and thought she was dirty but when I picked her up to investigate I realized she was just pale and that her comb had been pecked at and was bleeding (just a tiny bit). Sure enough there they had all laid and there were actually little drips of blood on one of the eggs I know this head hen gets REALLY anxious when she feels she needs to lay--she gets super loud and bossy--but drawing blood is a first. The rest of the time they all get along perfectly--there's a pecking order for sure, but there's never been blood. Besides caring for the wounds, should I be doing something else? Can you discipline a chicken? Is this infrequent behaviour normal and acceptable (within reason)? Thank you!!!