I have (had, she passed away night before last) a Gold star hen, about 5 months old. She got very lethargic and sick in March, then seemed to recover, but never laid eggs and couldn't get up to roost with the other hens. I thought she had started laying eggs last week, but was never positive. Day before last she was sitting on the floor of the coop, closing her eyes, very listless, with heavy breathing. I separated her and pet her and felt her, but I am an amateur and didn't know what to feel for. I dropper fed her ACV water and loved on her, but she passed away in the night. I was so curious about what could be wrong that we decided to autopsy. The following is graphic. Could she have been making a shell "cyst" these last 8 weeks? It is difficult to see, but there are rings in the white mass, like a gobstopper (sorry, couldn't think of anything else!) There were several of the cysts clumped into one that was bigger than my fist (I have a big fist!). They had a creamy, clotted fluid inside a small center. This was in her ovipositor. Looks and feels like a cooked yolk. Her heart seemed enlarged to me...Triangular, but excessively large at the top. She was making eggs, this is a "pretty" line up.