Start giving her Vitamin E! Get the capsules or liquid. I prefer the capsules. It's easier for me to pock it in their mouths than deal with the liquid. If you do the liquid? Be sure to put the syringe/eye dropper in the right side of her mouth. I kneel on my knees, place the chicken between them, squeeze just enough to keep them from escaping, lock your feet together to keep them from slipping out backwards and open their mouth. Insert the syringe/eye dropper towards the back of their mouth and disperse!
Cod Liver Oil is also a wonderful thing to give our chickens when they are sick! It helps them with their immune system. I take one capsule twice aday and haven't been sick in years! I learned about CLO by reading a chicken book when one of my hens got sick!
My Vet suggested I feed the chickens "medicated chick starter" at all times. It helps to prevent the sour crop problem.
If you have light colored chickens? Feeding them corn will also turn their feathers yellow!
I'm the one with the RIR ear problem. I've been thru the wringer myself trying to figure out poor Dorothy's problem until her eardrum burst. Then I knew it wasn't crook/wry neck.
Best wishes to ya!
TC