One of our three-month-old bantam chicks died today. She had been standing hunched over by herself for the past few days. Even when we picked her up she wouldn't sit down, just kept standing, hunched over and really puffy. Today we noticed that one of her sisters (possibly cousins or unrelated, actually, they just hatched together) has also started standing hunched up apart from the others. We have brought her inside and she is eating and drinking plenty (not sure how much she was taking in when she was out in the run), but she is colder and less energetic than she used to be. Does anyone know what is wrong, and how to fix it? We really don't want this one to die too!