Just today one of my barred rock hens (Frick) became very aggressive with another buff orpington hen (Rose). They are 19 weeks old now. Frick is very close to laying (her sister Frack started to lay 2 weeks ago) & has become very moody. Twice today she went after Rose (who, but the way is the same age but much smaller & physically less mature than the other hen). She was very nasty about it. Both times Rose was about 10 feet from her & Frick came running from across the coop & grabbed her with her beak & shook her & tore feathers out of her. I was right there so I grabbed Frick & put my hand on her back & held her down for a few minutes. About 5 minutes later she did the same thing. So I reprimanded her again. Is she just irritable because she is getting ready to tlay or do I have a big problem here? I have seen them try to work out their pecking order, but this was downright nasty & poor Rose does not even fight back.