When you take your havanese out for "bathroom break," stay out with them. If you're cold enough to go inside, it probably is too cold for your havanese to stay out much longer as well. Today is too cold to walk or have them out for an extended period.
When you bring a havanese in, wipe its paws and underside, making certain there are no ice balls clinging between the toes or on the sole of the foot. They can cause frostbite to your dog.