Growing up in Atlanta in the 1940s and 1950s, Susan Levine’s visits to New York City relatives included being the star of an impromptu novelty show: Her cousin invited over friends and charged 25 cents a pop for them to listen to Levine’s Southern accent.

Even though they too grew up in Atlanta, Levine’s two sons, born more than a quarter century after her, never spoke with the accent that is perhaps the most famous regional dialect in the United States, with its elongated vowels and soft “r” sounds.