This morning my (almost exactly) 5 year old barred rock hen wasn't out in her yard, and I found her sitting in the hay in her coop. She let me snuggle her (unusual, she usually resists contact) and she talked to me normally, and everything seemed to feel normal in her body, and no injuries. But I haven't dealt with any chicken issues before, so I'm not sure I would know. She started laying for the season about a month ago. She hasn't laid for a few days, but she sometimes goes that long between laying. We just have 2 chickens and her sister has been rooster-like, she crows and mounts her, and is the dominant hen. She hasn't eaten today, but I think she was eating normally yesterday. She walks a few steps then settles down. She's not acting broody at all. I have never vaccinated or wormed them. They are in a tractor on our backyard lawn and get moved almost daily, except when we're on vacation. They get laying pellets, oyster shells, crushed and baked egg shells from farmer's market (as they have aged, their shells have gotten thinner) and some produce scraps like melon rind and squash seeds. We have decided not to do vet care unless she needs to be euthanized. I know she's getting up there in age, but if she dies, I'm not sure what to do with the last lonely hen.