So glad to hear I’m not the only one who falls UPstairs; I frequently get to the top of the stairs, and try to put my foot on a step that isn’t there!
Best-ever incident was when I was in a school play. We had to march and cheerfully sing our way down the auditorium steps and then up the aisle. I can’t honestly blame ADD for this one, because who the heck can march in time AND sing out to the audience AND navigate their way down a flight of stairs? Well, everybody else in the play, I guess. 
But as for me, my foot hit the edge of the top step, and then that same foot skidded down the front edges of all the other six or seven wooden steps, and YET…
Somehow I managed to get the other foot down on the floor and keep on going, still singing! That came so close to being a literal “break a leg!” moment!
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