We have 5 remaining chickens. I got them from a real sketchy place in the country. His pens were tightly packed and he had chicks running everywhere and in pens. Quail, ducks, guineas, rabbits, peacocks,pigs etc.... Our runt died. One mutt chicken has been limping and not putting weight on her leg for over a week, she is slow acting and tries to stay up under the bigger chickens. Both the mutt chickens, one white with green legs and 1 that has the coloring of a quail have not grown. The white one, (Beatrice) is usually rowdy and a heck of a bug catcher (we put them in the garden during the day and a box in the garage at night while we build the McMansion coop, but she is trying to stay under the bigger chickens and is not acting right, she seems to occasionally gasp. Today she started limping too. Margreth, the quail looking mutt chicken, who has not grown either, has a closed eye and sleeps all the time, preferably under a chicken but if they are not available she will just sit down and sleep. Her leg has been gimpy for a week. Now Catherine, a Barrdrock, who has grown normally it seems, is gasping and peeping, she is sleepy acting and just not herself. We have been putting Apple Cider Vinegar in the water, plenty of outdoor time and organic feed. My sisters can't take another chicken dying. What is wrong with them?