Recently her buddy was killed by a predator and they came back for her but were unsuccesful. She was in a coop with her buddy away from our newer chickens. This was because she was trying to kill the chicks when they were little. So we reintroduced her to the flock by putting her cage in the coop for almost 2weeks then slowly integrating. They mixed well but she has not been right since the attack. We lost 2 chickens and still have no clue what did it. I'm not sure what is making her sick. She has no balance tonight and is having a hard time standing. I brought her inside to keep an eye on her. She keeps to herself away from the others and is not very energetic. Her poop is watery but she drinks lots of water. She has never laid an egg in 3yrs. Her color is pale and her neck skin is dry. Something is not right with her. And I just can't figure it out!! When she was attacked she lost all the nail on one foot. Please help!!!