Now that I am in my 3rd (4th?)(nth?) career, this one as an academic at the University of Maryland University College, I am lucky enough to be able to experience new events and learn new pieces of information.
One of the areas which has become apparent is the seemingly consistent relationship between the fragility of elderly grandparents, in particular grandmothers, of students around exam time.
Here is an article, from 1999, reprinted in a newsletter I very much enjoy reading called the Conversable Economist, which explains what is meant by this relationship and provides an explanation for why it happens.