I have 4 hens. A barred rock, buff orpington, blue cochin, and a leghorn. All of them seem normal enough and have been laying fine except for my little leghorn. She is 6 months old and is smaller then any of my other hens. She is not at the bottom of the pecking order, my cochin seems to be the most picked on, however she is very timid and scared of the other chickens. She eats, but I would say when my girls get treats, she almost never gets any because she wont fight for it. She also has a hard time flying, she sleeps on the ground because she can't get up to either of the low or high roosts and if she tries to fly from my hand if I pick her up, she lands chest first with her face in the dirt. It is the saddest thing. I have seen her land right a few times but not often. She also has not yet layed when all my others have started. Her comb is the largest and reddest and she looks healthy and clean otherwise. What could be wrong with my poor gimpy Gabby?