In the 1980s my Mother moved into my five bedroom home with my wife and I and my kids. She occupied one bedroom and certainly used "the facilities." There was absolutely no "public record" of this. (San Diego, CA.)It is of public record whether a residential house is declared as a two family home or one family home. ...
I currently reside in the Maryland suburbs of Washington Dc and were my mother or other relative move in with me there would be no "public record" of htis.
In both cases, I live or lived in a single family detached home.
If I owned a duplex and allowed my mother to occupy the other portion of those abodes, there would be a "public record" of the two dwellings.
Thus the simple, and polite, question, posed to the OP.