Henrietta not doing well

I picked up a RIR and 3 other hens about 2 months ago. The seller said that they were old enough, or almost old enough to be laying. I got a few eggs the first few days from what apears to be only one hen. Then nothing since from them. Anyway, since then I've added several other hens, all varying ages. Yesterday while feeding, (they free range during the day) I noticed that Henrietta was Over By the side of the yard by herself. The other chickens Usually come running when I call them. A few minutes later I noticed her standing near the water bucket and for several minutes was drinking from the water nipples. I mean several minutes! Forward to today. She is walking ok, but staying in the hen house. Still drinking a lot of water. Her crop feels like a half filled ballon. I was thinking that she may be egg bound, so I palpated her abdomen, and vent area. Could not feel anything there. I sat her up in one of the nesting boxes and offered her some meal worrms, which she did eat probably a teaspoon full of. Her head, face, and eyes look clear and normal. Any ideas?
Thanks,
Craig

I would check her crop in the morning to see if it has emptied. She may have just drunk a lot of water that made her crop full. If the crop is still puffy in the AM, you make want to massage it and keep an eye on her. The crop should gradually fill up during the day, and then empty overnight when they don't eat. One reason that your hens have not laid or have stopped laying is that they need about 12 hours of daylight daily to lay well. I use a single light in my coop that comes on at 5 AM, and goes off at 5 PM with a timer. It is normal for them to take a break during winter months without the extra hours of daylight.

She kept getting weaker and weaker since yesterday. I stopped by the Vet but they don't diagnose chickens. She passed away earlier today. Guess I'll never know.

Sorry for your loss. There are poultry labs in Texas that can perform a necropsy on a body that has been refrigerated, for a fee to try and diagnose her illness. You also do do one at home by opening her crop and abdomen to look around at organs, such as the gizzard (inside,) liver, intestines, and abdominal cavity for egg-like material.

I've had a RIR hen do this as well. She just faded very quickly, with little warning. I feel like the production birds are engineered to not live long lives.