When I got my first set of 12, I noticed one that was especially noisy and small. I took a closer look and discovered her eyes seemed closed. As though she couldn't find her food. She wasn't growing with the others. I kept a keen eye on her, began feeding the babes softened chick start with a little yogurt (hoping to get her to eat a little more) and even tried isolating her which made her peeping even more persistent. She made it, and today I can't tell her from the others who were 3 times the size she was. Her eyes were fully opened after another week or two. Either she was way younger than her siblings, or just a runt. I don't know what else to suggest, these are my first young ones. Good- Luck and keep us posted!