[1] She lived in both Beinn Bhreagh, Nova Scotia and Washington, D.C.[2] Grosvenor oversaw the steward ship of Bell's legacy Canadian estate at Beinn Bhreagh, Baddeck, Nova Scotia, until her death, and was also the Honorary President of the Alexander Graham Bell Club (founded in 1891), Canada's oldest continuing women's club.

[1] Grosvenor never married, had no children, but became the unofficial matriarch to about 60 nieces and nephews of several generations of Bell descendants at Beinn Bhreagh, Baddeck, Nova Scotia.

[5] In her later years she suffered from congestive heart failure but decided to stay on at the Bell estate due to her close relationship with the people of the community.

She had spent considerable time with him at both the Beinn Bhreagh estate and in Washington, D.C., as well as during his international trips, and was regarded as an authority on Bell to journalists and writers who sought greater detail on the scientist-inventor.

Pulitzer Prize winner and biographer Robert V. Bruce, author of the most authoritative work on Bell, described him as having "the majesty of Moses and the benevolence of Santa Claus."

There were many joyful occasions when his grandchildren would sit on his lap and, on command, tweaked the nose of Bell "to produce a dog's bark, pulling his hair for a sheep's bleat, and by way of climax, tugging his Santa Claus beard for the deliciously fierce growl of a bear.

Dr. Bell later wrote: "I almost forgot to mention the witness who will probably live the longest after this event (and remember least about it) — my little granddaughter Miss Mabel Grosvenor — 2 years of age.