My friend Sherilynne’s grandfather with his sons, 1950s, Malaya (now Malaysia)
For other minor characters who are not relations, it is usually best to refer to them by the role they play in the story.
For example, refer to your “first-grade teacher” if that person only appears a few times. However, if a character appears more often, this becomes awkward. It can also give the impression that you’re hiding something. In that case, it is better to give that character a proper name and introduce him as “Mr. Frey, my first-grade teacher.”
The same should be done to reorient the reader if someone only appears sparingly throughout the text. So you could say “our housekeeper, Mrs. Burns,” when she shows up again, instead of expecting the reader to remember who Mrs. Burns was when she appeared ten chapters earlier.
Multiple people with the same name is often an issue in family stories.
If you are dealing with multiple “William Kellers” (an example from the American side of my family), providing middle initials, or “Jr.” doesn’t cut it. In an story you usually refer to main characters by first name, so you might have to resort to nicknames “Bill” or “Billy.” If that’s not acceptable, you could resort to “Uncle William” and “Cousin William”–some identifier that helps the reader keep them apart.
The fewer words you need to clearly name someone, the better.
For a main character, for example, “Billy” makes for an easier text to follow than “Brother Bill.”
Beta readers can be very helpful in giving you feedback when they got overloaded in keeping track of characters. As the writer, it is hard to tell which characters readers will remember and when they might get confused. Ask your beta readers to indicate where they would appreciate being reminded of who someone is.
Prompt: Write about how you got your name, whom you are named after (if you are), and why.
My book How to Write Compelling Stories from Family History is full of advice like this. For a list of 10 unusual prompts to get you started writing stories from family history, sign up for my newsletter.