Any of these could have been her death from 1901, when she was in the census, to 1950:

Surname   First name(s)   Age   District   Vol  Page
Deaths Jun 1906   (>99%)
Vaughan Mary 55 Cardigan 11b 2
Deaths Mar 1908   (>99%)
VAUGHAN Mary 58 Conway 11b 390
Deaths Mar 1910   (>99%)
Vaughan Mary 59 Abergavenny 11a 35
Deaths Jun 1912   (>99%)
VAUGHAN Mary 62 Sheffield 9c 618
Deaths Dec 1916   (>99%)
Vaughan Mary 66 Pontypridd 11a 675
Deaths Jun 1923   (>99%)
VAUGHAN Mary 72 Godstone 2a 260
Deaths Mar 1928   (>99%)
Vaughan Mary 76 Birmingham S. 6d 81
Deaths Mar 1929   (>99%)
Vaughan Mary 78 Burton 6b 608
Deaths Sep 1929   (>99%)
Vaughan Mary 79 Wolverhampton 6b 473
Deaths Dec 1933   (>99%)
Vaughan Mary 82 Cardigan 11b 4
Deaths Sep 1934   (>99%)
Vaughan Mary 83 Kensington 1a 91
Deaths Sep 1937   (>99%)
Vaughan Mary 87 Aled 11b 318
Deaths Mar 1942   (>99%)
Vaughan Mary 91 Aled 11b 819
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