I have a white leg horn who is about 4 years old she is super skinny right now with a droopy comb and a dirty but. She's had problems in the past but always got better but I'm afraid she won't this time. She is the only one that is sick, we got her some vitamins today, I haven't given them to her yet but I'm wondering what I can do to fatten her up. Winter is coming and its already pretty cold and I don't want her to freeze. Any suggestions?