The hen made it through the night. She is eating, scratching, walking, standing & preening herself. She just isnt raising her head. She can stand upright, but cant raise her head upward with beak pointing to the sky. So it looks like she is always looking down. The other two chicks can lift their heads up & look at my hand when I put it in their brooder. The 'sick' chick doesnt. What can the problem be???