What do her droppings look like? She could be suffering from possible coccidiosis, which is a common illness in chicks up to 20 weeks old. Symptoms are lethargy, standing hunched or puffed up, not eating, runny droppings with blood or mucus. Corid (amprollium) in the water is the treatment. Dosage is 2 tsp of the liquid, or 1/2 tsp of the powder, per gallon of water for 5 days. Afterward, give chicken vitamins and some plain yogurt for a few days. Until you can get Corid from a feed store cattle section, someone needs to feed her water with electrolytes by dipping her beak or giving it with a syringe or dropper. Pedialyte, Gatorade, or sugar water will do in a pinch. She could just be dehydrated, or something else may be wrong, but with chicks her age, coccidiosis can be deadly.