(Not quite sure where this originates from, whether from the Inuit of northern Canada...or from the Australian Native People)
But I am fascinated by the expression "A Three Dog Night"
It means that for every 10 degrees below freezing, you had to have a dog in bed with you to keep you warm. A three dog night meant 30 below freezing.
So the colder it gets the bigger bed you need by the sound of that!!
(It doesn't say anything however about dog breath in the morning!)