I always took Kirby up stairs with me since hed whine if i left him downstairs an id block the stairway off with a baby gate. well one time i went downstairs to go the bathroom an few moments later heard a super loud crash an when i stepped out into the living room i seen my dog who was supposed to be upstairs now downstairs looking as confused as i was to what just happened.

somehow he had managed to get up on shelf we have in front of our stove pipe an fell through stove pipes cutout thing to the room below which is a good 7to 8' drop.
got so lucky that it didnt hurt him but needles to say after that i always took him downstairs with me if i had to leave for any reasons