Stairs are challenging enough for adults at times, but I distinctly remember how hard it was to climb them when I was little.  When you are small in stature, 7″ high risers hit at mid-thigh and most of the time you have to take each stair on all fours.  Many of the epic, all-out “Alli versus the Stairs” battles ended with a small, defiant child celebrating wildly on the second floor, but sometimes things didn’t go my way.  On the days that the straight run, open tread, carpeted monster was …