one of my 6 new birds is acting a lot less active then the other 5. They are about 2 months old.they have been living in the same run (separate Coop) as my 3 mature hen's for about a month.every thing has been fine until yesterday when this one is not moving around much. She is just standing, closing her eyes and not scratching for bugs or anything. She walked to the coop at dark and came out this morning and drank. She is still acting the same. I'm worried about her. Should I be?