Question: When was John Gardner Coolidge's aunt born?

Context articles: Never Send Flowers
The Stevens–Coolidge Place
John Gardner Coolidge
John Twiname Gardner
SeaFire
John Gardner (Texas Ranger)
Tomorrow Shall Be My Dancing Day
Isabella Stewart Gardner
Death is Forever
Cold (novel)

Never Send Flowers, first published in 1993, was the thirteenth novel by John Gardner featuring Ian Fleming's secret agent, James Bond (including Gardner's novelization of "Licence to Kill").
 Carrying the Glidrose Publications copyright, it was first published in the United Kingdom by Hodder & Stoughton and in the United States by Putnam.
The Stevens–Coolidge Place, formerly known as Ashdale Farm, is a garden and historic home located on 91 acre at 139 Andover Street in North Andover, Massachusetts.
 Helen Stevens Coolidge's family first acquired the farm in 1729, and from 1914 to 1962 it was her summer home with husband John Gardner Coolidge, diplomat, descendant of Thomas Jefferson, and nephew of Isabella Stewart Gardner.
 It is now a nonprofit museum operated by The Trustees of Reservations.
John Gardner Coolidge (July 4, 1863 – February 28, 1936) was an American collector, diplomat, author, and nephew of Isabella Stewart Gardner.
John Twiname Gardner (2 August 1854, in South Molton – 15 February 1914, in Kensington) was a general practitioner and composer of much published parlour and light music.
 From 1888 to 1903 he worked as a family doctor in Ilfracombe, North Devon, where he conducted the local choral society and was generally a mainstay of musical life in the town.
 He was the grandfather of the well-known composer John Gardner.
SeaFire, first published in 1994, was the fourteenth novel by John Gardner featuring Ian Fleming's secret agent, James Bond (including Gardner's novelization of "Licence to Kill").
 Carrying the Glidrose Publications copyright, it was first published in the United Kingdom by Hodder & Stoughton and in the United States by Putnam.
John Gardner (1845–1926) was a Texas Ranger, cowboy, Indian fighter, and noted trail boss who was the subject of a folklore song titled, "John Gardner's Trail Herd".
 It was often alleged that Gardner was a member of the Sam Bass Gang.
 He was the father of Joe Gardner, a noted World Roping Champion.
Tomorrow Shall Be My Dancing Day is an English carol usually attributed as 'traditional'; its first written appearance is in William B. Sandys' "Christmas Carols Ancient and Modern" of 1833.
 It is most well known in John Gardner's adaptation, but numerous other composers have made original settings of it or arranged the traditional tune, including Gustav Holst, Igor Stravinsky, David Willcocks, John Rutter, Ronald Corp, Philip Stopford, Andrew Carter, Jamie W. Hall and Jack Gibbons.
Isabella Stewart Gardner (April 14, 1840 – July 17, 1924) was a leading American art collector, philanthropist, and patron of the arts.
 She founded the Isabella Stewart Gardner Museum in Boston.
Death Is Forever, first published in 1992, was the twelfth novel by John Gardner featuring Ian Fleming's secret agent, James Bond (including Gardner's novelization of "Licence to Kill").
 Carrying the Glidrose Publications copyright, it was first published in the United Kingdom by Hodder & Stoughton and in the United States by Putnam.
Cold, first published in 1996, was the sixteenth and final novel by John Gardner featuring Ian Fleming's secret agent, James Bond (including Gardner's novelizations of "Licence to Kill" and "GoldenEye").
 Carrying the Glidrose Publications copyright, it was first published in the United Kingdom by Hodder & Stoughton and in the United States by Putnam.