When I got my hens they all would roost, but I recently noticed one that has made a little nest in the straw on the grown and she isn't roosting anymore. At first I wondered if she was broody but she goes out all day, she does lay in it, and sleeps in it the next night, but doesn't stay in it during the day. I looked her over and didn't see any external issues, is there a reason she may not be roosting?