When I was about six years old, I made friends with a boy named Danny. At the lake community where our family spent our summer vacation, the house where Danny's family stayed was right across the street from the house where we stayed. Because we were not year-round neighbors, the families did not know each other at all, but Danny and I eventually met and began to play together.

One day, when we were playing catch together, the ball got away from us and rolled over near where my sister happened to be sitting. Not knowing my sister's name, Danny called out to her, "Hey, David's sister, could you please toss us that ball?"

My sister, who was seven years older, was amused by the appellation, and so it stuck. From that time on, among the kids in the two families, she was known as "David's sis…