propane heater in trailer while traveling

In defense of the dog: A dog that is a "house dog" and not an "outside dog" will not have the thick fur coat like an outside dog will in the cold winter months. Outdoor dogs get acclimated to the temperature changes and their coat grows or sheds accordingly. To put an indoor dog, outside, in cold weather ... yea ... the dog is going to be cold, could get sick, catch a cold, or even worse.

I applaud the OP for wanting to protect his dog!