We have got 4 bantams, one japanese, two normal, and one partridge bantam. Initially they were free range for the first 4/5 months we had them, but they got more adventurous and started wandering onto the road, so we built a large pen for them, including their run. The pen was behind some bushes so they have a lot to scratch around in.
I noticed about 2 weeks ago that one of the normal bantams pecked/midly attacked the other. They are of the same size, and breed, and the other two bantams were not involved at all.
Today, I went to go clean them out, and one of the normal ones was dead, on it's side. It sort of had it's legs up in the air, as if it had had a shock?
The others were in the coop, and I wanted to know why the chicken died? Was it bullying, shock, or illness? I'm really confused about it. pets question and answers,www.5d2d.com
Also, the chicken that died had a cataract which we noticed about 2 weeks after we purchased them all. In the last few months they have pretty much all stopped laying apart from the one I suspected was bullying the dead one.u

Please please please answer for me! Thankyou so much.

It sounds to me as if the one who died had been sick for some time, and the other one realised this and started bullying her because she sensed her weakness. Chickens are very stoical when feeling ill and show few signs of it until they're really feeling bad, as to let the others see they're unwell is an admission of weakness and the others may then pick on them. If any of your hens in the future shows signs of abnormality, such as the cataract you mention, it might be wise to get it checked out with the vet, or in the case of one you'd only had for two weeks, take it back to the breeder for an exchange or refund. pets question and answers,www.5d2d.com
Sometimes chickens do just die suddenly from heart attacks, and possibly this might have happened to yours. If so, there wouldn't have been any signs beforehand and in no way would it be your fault for not caring for her. However, if they've all stopped laying and are not very old, maybe something is going on with your feeding or cleanliness regime to stress them in some way. Have you checked them all, and their housing, for lice and redmite? Have you wormed them with Flubenvet within the past 6 months? If thery're infested with parasites or worms, they'll lose condition fast and one of the signs will be that they'll stop laying.

In a pack of any animal there is a dominant animal. The most strongest male or female will dominate the others. In this case one of your dominant chickens figured out that that chicken was weak and vulnerable. And killed it because to them its one less bird to compete for food with. This chicken could have also been carrying a disease and they figured it out and killed it good luck.