Yesterday I noticed that one of my Ameraucanas (2 months old) was keeping her distance from the rest of the flock. She'd walk slowly behind them and then puff up her feathers and tuck her head under her wing. She seemed abnormally lethargic. This morning she didn't run out of the coop with the others when I opened the door, but stayed inside- I went back out to check on her and found her at the bottom of the ramp from the coop kind of flopped over and shaking. I've taken her inside away from the rest of the flock but am not sure what is causing this or if there's anything I can do? She's just sitting here shaking and can't seem to right herself. I'm having a horrible chicken week so far, I'm really hoping this girl makes it through and that it isn't something the rest of the flock can catch! Any insight or help would be greatly appreciated!