My Great Aunt Nola was a professor of calculus at the University of of Missouri in Columbia.  At least a couple different family members stayed with her while attending MU, including my Mom.  A story I remember her telling was that she helped paint a room one day.  Nola used exactly the same color as it already was and Mom couldn’t see where she had already been, except for the sheen of the wet paint.

These were taken in 1980.