About a week ago, one of my buff Orpingtons started hanging out in one of the nesting boxes. My fella and I thought she was broody (and maybe she is...) but we live in Western NY and the weather has been hovering around 0 since she's been in the nesting box all day and night. She makes a soft weird clucking noise and puffs up her feathers when we lift her to get eggs. Today she clung on to the nesting box edge when I tried to get her out for food... Yesterday, I noticed frostbite on her comb but not on anyone else's comb, maybe because moisture collects and then condensates in that little box, but not in the coop as a whole. When I threw her out of of the box to eat this afternoon, I noticed that the other chickens behaved differently toward her, squawking loudly when "broody" came near or pecking her head when she went to eat from the trough. She eventually ate and drank, and then flew back into the nesting box, much to the squawking of another hen who appeared to be about to lay. I also noticed a dark crustiness (like gray/black boogers) on her beak just below her nostrils. It could be dirt I guess, but that substance on her nose, her lethargy, and most importantly the other girls' trying to stay away from her makes me wonder if she's more than broody and frostbit. I've never had a broody hen before, so I have a few questions for you all: 1. I read about petroleum jelly for preventing frostbite, but what about treating it after it starts? Her comb and wattles have white, but are black tipped. 2. She wants to be in the nesting box, which I think is leading her to be frostbit. Any ideas? 3. Wih the collection of symptoms (lethargy/broodiness, crusty gunk on nose, reaction from other hens, frostbite) should I consider an illness? Suggestions for interventions?