Have 14 hens, been together for years. Yesterday saw one of the white ones laying on ground and when she got up a couple others jumped pecking at her head til she just laid down . I move her outside and she was moving around some.. Last night put her in a old pen with food and water, she was eating and drinking. This morning she is just sitting on ground looking around. Any suggestions as to what caused the others to attack her and can she go back to flock???