On Friday morning I opened the coop for the girls to go in their run like every morning and all six of the girls seemed fine. They were all eating and their activity was normal. I had something I needs to do for church and my husband didn't get home till late that night 12ish and he went to close the coop. It seemed that all the girls were in for the night. And when I went to let them out Saturday morning I noticed there was only five. It turns out one had passed away earlier before it got dark. I found her in a corner of the run. She didn't have any marks that she was a attacked or pecked from the other chickens. I wasn't sure if anybody has any ideas what could of caused this to happen. Also when I checked on the girls before I left for work one of the chickens combs is looking pale and I'm concerned she may pass away as well. She was acting fine when I left for work. She ate when she came out of the coop and was being very active. On a side note they have all been laying their eggs. Occasionally I'll get five eggs instead of six.