I have 6 chickens. All of them are 8 mos old. One of the wyandotte's, Winnie, suddenly died yesterday. We found her when we got home from work. Winnie was the only chicken currently laying eggs. None of the others have started laying yet. Winnie was very healthy. She was a good eater. I was feeding them the medicated feed until about 6-7 months, then switched over to the laying pellets. I supplement their diet with oatmeal and raisins on the weekends, plus some fruits or veggies that interest them. I inspected her body before we buried her and I could find nothing visibly wrong with her. She had beautiful, healthy feathers. She was an excellent size too. One of the larger of the 6 birds. I'm completely baffled by this. There is no sign that a predator was involved. The other girls appear to be fine, and the coup/run was undisturbed. Should I be concerned for the remaining 5 birds? What could have caused this? Thank you for your help.