Hi, I am new to keeping chickens and have 2 x10wk old (Plymouth Rocks & Speckled Sussex) and 1 x 5 week old (light sussex). The SS is my concern, she seems very small, the 5 week old is now bigger than her, her feathers look a bit manky around her face (this could just be her coloring but her feathers don't seem as good quality as the others). She eats more than the other two and sleeps more than the other two. I see her regularly stretching neck, shaking head and yawning but due to my inexperience I am not sure if this is normal or not. Because I don't see the others do it very often I am thinking its not right. Here are a couple of photos. She seems pretty happy roaming and is always active around the yard. Any advice is helpful, thanks.