our flock of 8 did great last winter. No problems no deaths. In the spring we added 6 more to the group. They are well migrated together. This winter they seem to have forgotten how to winter. The other week my husband went out to collect eggs and check on the, he dose this about 8pm or so when all of them are in for the night. He found on of the out side of the coop huddled up and a little frosty. So he got her all good and situated and she’s fine. Hasn’t done it since. This one one of the ones from the first flock. So she has been through a winter already. The other night he goes out everyone is in, accounted for and snuggled up. He goes out in the morning to let them out and one of them left the coop in the middle of the night, went behind their food bin and died. We have not noticed any health problems and think it was the cold that got her. But why would she leave the coop in the middle of the night and stay out long enough to freeze? Why would she not go back in?