They do both have kennel cough, Maggie just has a more serious case of it. That's probably why he called it bronchitis and gave her anti-biotics.

Kennel cough is airborne. It can be carried a long way. My dogs got it a couple years ago from a dog yard 2km away. Generally, just like a human cold, KC runs it course and leaves no permanent problems. Takes a couple weeks to fully resolve. Hopefully your dogs will be feeling better soon.