Hi All - I am a new chicken mommy - we moved into this home that came complete with 4 adorable hens that I am in love with. They have a nice coop that is covered on top with mesh wiring to prevent predators and the sides and has a run around it also protected on top and sides. It is starting to get cold up here in NJ and I noticed that the girls are sleeping on the roof, not inside the coop. I worry that they will freeze over the winter. They were just hatched in March so they don't know how to do this anymore than I do LOL. Should I just put something on top of the roof so they don't sleep up there or just let them be since they are safe from predators?