This chick most likely has a broken neck. It would be best to put it down. This chick will not be able to eat or drink properly even if it makes it to adulthood. sorry for your loss.
Wow, looks to be a hard winter this year! first, with your brahma, it is very strange she is acting this way, I don't think it's from the cold, but that may be part of the problem, she may have been weakened by the cold, and would have a intestinal problem. But lethargy is usually not from the...