I need some help. I have a hatch of 13 chicks that are 7 weeks old. I lost 1 Faverolle chick last week for no apparent reason, she stopped eating and lost condition rapidly and died within 2 days. This morning I noticed one of the Salmon Faverolle pullets is not eating or drinking and is just fluffed up sitting on top of a bale of hay. The hatch have been outside and off heat for 2 weeks and the rest of the chicks are all ok. I've checked to make sure their are no mites and added some ACV to their water. I'm still pretty new at chick raising so need some advice on what the problem could be.