I have a 20 week old partridge Cochin. She is very sweet and follows me around when I'm out there. The last four days she seems a little slumply. Feathers downward and very docile.. almost shy. At roost time she sits on the floor instead of sitting in her usual spot. She doesn't seem to be growing as fast as her sister and has recently started getting picked on. I isolated her this morning to see if everything looks normal and other then her head down slumpy behavior she's eating and drinking and poop seems normal, but standing next to her sister you can definitely tell she's not maturing like the she is?