The year I was in the fourth grade, my grandparents came to Chicago to stay with my sister and me while Mom and Dad went to Florida for a meeting. When my folks came home, Granny pointed to me and proclaimed, “This child can’t see!”
It seems she had noticed that I sat close to the TV and squinted a lot, especially when I was reading, which was most of the time. Apparently a conversation with my teacher confirmed Granny’s diagnosis. This being ages before one-hour opticians, it took about two weeks before I had my first glasses.