Frack is a dark Brahma hen, about 8 or so years old. She has been my friend since the day she hatched. She is housebroken and comes inside to lay her eggs, although in recent years she has only been laying occasionally. She still comes inside every day to visit and for a treat, as she did yesterday. I saw nothing to make me think she was sick. This morning when I opened the coop doors, Frack did not come running out. She was in her corner (she always sleeps on the floor, being too big/lazy to jump to the roosts). Her head was hanging down. I picked her up and put her in the middle of the coop. She staggered a step or two, but then wouldn't try to walk. Her weight is fine and she has no symptoms except for her head drooping. She can't seem to hold it up. I'm not sure what to do. Any suggestions?