I have a buff orpington hen who isn't doing well, and I am worried. She is about 6 months old. A few days ago (maybe 5?), I started to notice that she was walking close to the ground and then sitting in the yard. She can get herself around - rather quickly, too, in a burst - but as she sits, she starts to tip forward (meaning her butt rises into the air like there is a balloon attached to it) until she loses her balance and falls on her side. When she is on her side, she stretches one leg out straight. She can sometimes get herself back up, but not always. She is using both wings, but i think one side is stronger than the other. She is eating and drinking, and, like i said, she is still mostly getting herself around. Today wasn't a good day, and when i went to check on her, she had been laying in the mud. I gave her a bath (which she seemed to like) and dried her. I don't see any issues with her feet, and she uses both legs when in my arms to grip or move about. I am giving her vitamins, but i can't figure out what is wrong. Any thoughts? Thanks so much for any help you can give.