My hen Marjorie (a Welsummer) has a strange growth on her chest. She isn't the friendliest chicken and won't let me get near her. I didn't notice this on her a few days ago, but then I wasn't closely looking. All of my other girls are fine. What should I do?! I don't want to put her down. Maybe just wait and see? Has anyone else had something like this happen to their hen?