DC rear windows always fogging

No matter how I run the up front controls they are always fogging/frosting up. These are the door windows not the rear back glass. I dont think i need to run the AC the floor mats are not wet back there (2 young kids in car seats)

Frustrated.

 

Kids ( or anybody ) breathing next to the windows will cause this. In any car. It is cold outside the glass, warm humid breath on the inside of the glass causes condensation.

I usually run the AC and turn up the heat dial, this reduces the humidity inside the truck enough to keep the windows clear.