One of my hens is unwell, she has loose stool, seems generally weaker than the other four and weights lighter, so I decided to separate her and give her extra food hoping that she's put on some weight and gain strength. The problem is that whenever I open her cage so that she can come out out for a stroll, three of the other hens constantly chase and attack her. Have you experienced a similar scenario? If yes, how have you dealt with it?