Just for background info really
Family Search has this entry
Barbara Vaughan Age: 90
Relationship to Head of Household: Mother
Birthplace: Penmachno, Carnarvonshire
However - the 1891 image reads as follows - all b Penmachno
Morgan Roberts 54
Sydney 54 wife
Margaret Vaughan 38 sister in law unmarried
Barbara Roberts 90 widow mother
Mary Hughes 21 servant b Trawsfynydd, Merionethshire
RG12 Piece 4634 Folio 7 Page 9
Morgan married Sydney Vaughan in 1872 but 1871 census shows him living with mother Barbara Roberts nee Vaughan - see link below
https://familysearch.org/pal:/MM9.1.1/FGW1-Q62