I have ten chickens about two years old and raised together from the start. Two are Barred Rocks. Last winter around Middle December, one of them was just sitting outside not eating or drinking and couldn't even walk. She had watery poop too. I brought her indoors and had her in a crate and treated her with oregano oil in her water. After three weeks she had regained her health and was able to return to the flock. At first they hen-pecked her but by the end of the day it seems she had been accepted back in. I noticed she was getting thinner over the past few months and when I picked her up she is like bone with feathers. She seems healthy otherwise. Eating and drinking. None of the girls seem to be mean to her except I noticed that she is not roosting with them at night. She roosts alone while the others settle together. Granted it is still want here but... That's my concern. I'm worried that when the temp drops in the winter she won't be able to stay warm enough at night. She literally doesn't have any meat or fat on her. What can I do for her??? How can I get her to gain weight??