I know films and historical accuracy are, unfortunately, enemies, but a couple of years ago I saw a film that included a family living in close quarters in a cabin and they all slept on cots on the floor to the exception of the parents.
Recently, I looked through some pictures of real life (old) cabins and they featured bed structures that kept the mattresses / cots off the floor.
Was there a reason for this? Was sleeping on a cot on a cabin floor too cold (at least in Canadian and Alaskan winters) in real life? Or would big families have beds only for some and the rest would really sleep on the floor?