I have a group of 6 orpington/easter eggers about 3 months old. On Monday night, I picked one up. She was so thin! Tuesday morning she was dead. I checked the others. 2 others are thin. 1 of the thin ones had a bump on eyelid and beak. Today they are lethargic, just sitting and isolated. I thought I saw a nasal or mouth drip on one without bump but not positive. Any idea what is going on and how I can save them?