We have 6 girls, and they are all approx. 10 months of age. Up until now they have gotten along swimmingly. We left for two weeks at Christmas, our neighbor watched the girls and when we got back commented that our Buff O seemed broody and wouldn't leave her nest. The last three days have confirmed that. She won't leave her nest unless we physically remove her which we have done all three days. Each time I removed her and put her with the flock she was immediately chased by at least 3 of the 5 other hens. Chased and pecked at. Yesterday I noticed her comb was being pecked at and had some dried blood remnants. The coop design is 4'x4' and there has always been enough room for all 6 to sit on the perch. I checked the protein content of their food after noticing that as a cause in another post, and our content is 16%. The weather here has been unusually cold -- sitting in the 20's. I have the light go on right before dark and then it remains on for 6 hours (4:00 - 10:00). The Buff O just stays in her nest -- she doesn't even roost. Sits in the nest backward so her bum faces the coop. My biggest concern is that in 3 days we leave for a month and I won't be near to watch/help. I can give advice to our friends watching the chickens but I am concerned for her welfare when I go. Thanks for your help.