From elsewhere ...
“Many African Americans object to the term “Uncle” (or “Aunt”) when used in this context, as it was a southern form of address first used with older enslaved peoples, since they were denied use of courtesy titles.
According to The New York Times, “white Southerners once used ‘uncle’ and ‘aunt’ as honorifics for blacks because they refused to say ‘Mrs’ or ‘Mister’.”
According to The New York Times, “white Southerners once used ‘uncle’ and ‘aunt’ as honorifics for blacks because they refused to say ‘Mrs’ or ‘Mister’.”
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Chinese use “aunt” or “uncle” as honorifics to show both respect and love toward someone where the person is not actually a relation. A young child might refer to an older neighbor As Auntie Mary, for example.