Stroke of fate

My father in law was hospitalized yesterday. He suddenly had purple spots all over his body. It seems that his blood platelets had become suddenly zero, which is serious because if he gets internal bleeding no one can stop it. My sister in law said it was one of the most intractable but not incurable, according to the doctor. We can't do anything but to place our hope on the doc's word.
This way, a stroke of fate lies in ambush and blindside us. It brought home to me.
We are leaving home to visit him.