It is sad when we lose a chook, especially when it is old age, they have been with us a long time, and sad to say goodbye. Cold does not really harm birds, but if they are wet and cold, this is a disaster in the making, just like anything, cold, can bundle up (lots of feathers on them thar cochins), but wet and cold...I would presume she was not wet, probably not really cold either. But of course, as we all know, as age comes, as does the lower defense against cold. Maybe it was just her time. I think if it was illness, there would have been other symptoms. Sorry for your loss, but do be aware of the gapeworm. It is not overly common, but generally is much more a happening when the weather be comes moist in the fall. Have a wonderful day, I mean that, find something to make you smile, there are many things....CynthiaM.