Poor thing! She's noticeably smaller than her sisters because she isn't able to eat or drink very effectively, though she's tenacious and keeps trying.
I found a good website that talks about the condition, which it seems is linked to a vitamin deficiency. Her parents probably had it and passed it on to her.
This site says the chick needs supplementary vitamin E. So yesterday I went and got vitamin E tablets as well as some shelled sunflower seeds, which are a good natural source of the vitamin.
Last night I cut open some of the vitamins, squeezed the liquid into a dropper and mixed it with some warm water. I tried feeding the baby some of this mixture with the dropper but she wouldn't drink much.
Next thing to try- separating her. The website said being with the flock can stress out or injure the chick (the others might trample her when she's stuck with her head back). It's good to pull them out but keep them close so they can still hear each other. They suggested putting a soft toy in with the chick so it doesn't feel alone.
This was my solution:
I made a separate brooder, right next to the one for the other chicks. I put the little wry neck girl in there with two other chicks so she wouldn't be alone. I added some chopped sunflower seeds to the food dish and a little vitamin E to their water.
Initially when I put the chicks in, they stood huddled together in the middle of the container chirping loudly. It didn't take more than a minute or so, though, for the wry neck girl to find the food dish and begin chowing down. She seemed so hungry! And she was picking out the sunflower seeds. Maybe part of the issue is she has a hard time getting into the feeders in the main brooder because she is smaller. Anyway, I just got an update from Josh, who said she is eating voraciously and seems steadier on her feet.
Hopefully we are on the right track to get her well again and growing. I'll keep you posted!