Moody (agressive hen) with a possible eggbound hen? what to do??

[CT Chickens]

I have 6 Buff Orphingtons and 1 RIR, 1 red star, 1 white leg horn and 6 chicks (3 barred rocks, 1 arecauna cross, 1 golden comet cross, 1 speckled sussex). I have had my chicks for just over two weeks now and they are 6-8 weeks old. This morning I went out to let my hens out and I noticed one of my chicks' head was pecked at. Pretty bad where there is no more feathers left on their head. Last night when I closed them up for the night There was no peck marks and the chicks were in their hutch, my suspcision is that it happened this morning. Once I let the hens out I noticed my RIR darted right to one of the other chicks and pecked at it hard enough where the chick 'screamed' and the hen took feathers. The attacking hen has had a history of being aggressive to me and now I am worried with the chicks because she will make a be line right towards them. What does everyone think is going on? She has a history of attacking one of my BO in the same fashion. Is this typical behavior of a RIR?

Also, my red star has been fatigue and she is drinking but eating very little. All she wants to do is sit. I have felt her bottom and it feels as though she has an egg stuck, she is one of my layers and she hasn't layed in a few days. She hasn't had any normal BM's, just like a watery discharge that will alter from a black/ green to a yolk color. I don't want to stress her out any more so but I have tried massaging her bottom to see if i Could work it out but there is no relief. When she walks she has been carrying her bottom to the ground as opposed to up. I have also tried yogurt and oatmeal and she turned her beak up to the yogurt and the oatmeal she pecked at. She has been going in and out of the roosting boxes as though she wants to lay an egg but there has been nothing. This has been going on for the last three days now. Could she be stressed with the chicks? (She doesnt see bothered by them, she actually prefers to be with them) Any suggestions?

 

[CT Chickens]

I also should add the questionable eggbound hen's comb isn't as red as it used to be and is more so floppy with a spot around it. Her backside is very warm to the touch.

 

[chickenzoo]

I would seperate the RIR before she really injures one of the girls. She seems like a bully. The other does seem egg bound. You can try squirting mineral oil into her vent, or olive oil etc.. To try and get the egg to loosen. Warm baths with the hen sitting up to her vent helps relax muscles to pass egg, also feed calcium to help. It needs to come our soon, keep massaging. Worse case is you will have to try and break the egg and flush out the pieces and put her on antibiotics... And see if she makes it.