I have 5 GLW's all about 3 months old. Blanche, my biggest girl, has all of a sudden developed a hard time standing in one place for more than 30 seconds and kind of walks a little wobbly. My biggest concern is that she plops down every few minutes. I've been monitoring her all morning (noticed this last night just before dark) and she still walks and runs occassionally, I also saw her jump/"fly" a few times. But she will kind of fall back on her hind legs and then plop down when standing in one spot. Her fingers will sometimes be curled up while this happens too, but not every time. And she doesn't seem to be able to balance on one leg. She also will go lay down in shade or coop while the others free-roam. She will then go join the others after a few minutes of laying down. I offered them treats, corn and zucchini. I do give them too many treats like this, I know now to limit that. Blanche did eat a little but she didn't come running at first sight of treats and I don't think she ate as much as the others. The other's don't seem to notice, I don't see any bullying signs so far. PS: all the other chickens are fine and show no such symptoms. Any suggestions on what I should do to help her? Or even on what this could be caused by? Thank you!