I recently bought 10 chicks from a local chicken rancher. One almost immediately showed signs of illness. Lethargic, then wobbly, doesn't seem to be able to stand properly, rocking back on her feet instead of standing upright, some twitching, and she sounds like she is congested. She eats and drinks. All the others seem fine. This is my first stab at having laying hens so am completely in the dark here! Any help is appreciated!