This is our first year raising chicken. Have question that I really need answered. I have a flock of 15 mixed hens Jersey Giants, Barred Rock and Easter Egger mixes. All girls are doing fine except 1 Jersey giant does not want to get off roost once the door is open. Everyone else rushes out the door except, but once we take her off the roost and set her at the door she heads out and interacts normal with all the others. Any Ideas????