I have one hen out of 6 that are laying that produces only rubber eggs. They have oyster shell available at all times. The others have nice hard eggs. This hen has always been a bit different, a runt and slow to develop. Yesterday she was looking sickly and a mess on her backside with feces and egg yolk. She looked as if she had a bit of a prolapse as she was sticking out. I took her in, gave her a bath and pulled out the membrane of a broken egg. She seemed to love the bath and after ate a hearty meal of chick crumbs with yogurt, a crushed up tums, cod liver oil and boiled egg. She stayed in the dog crate overnight and was looking back to normal today, so I released her back out with the rest. No prolapse, no feces on her feathers, back to normal poops, scratching around. Now, my question is, is there a way to help her lay normal eggs? My husband doesn't want to keep her if she will only lay rubber eggs. Is it caused by bad genetics? They get lots of light, the morning sun shines in the coop through 2 large windows that take up most of that wall and they are free range from early morning until night. Plus, she is the only one affected. Any suggestions?