Scottish History Society's Third Series, Volume XXI, Miscellany (fifth volume) pages 196-290 contain the article: "Letters to John MacKenzie of Delvine, Advocate, one of the Principal Clerks of Session, from The Revd. Alexander Monro, D.D., sometime Principal of the University of Edinburgh, 1690 to 1698". As interesting as those letters are, there are issues of a genealogical nature within the introduction which require to be addressed and corrected. The author of said Introduction, William K. Dickson, states the following:
Evidence, proves the following points:
- That MacKenzie's first wife was not named Isabel Lentron, but rather she was Helen Lentron;
- She was buried in the Greyfriars, Edinburgh, on 27th December 1685, twelve days after their son's baptism, therefore, her death was not within weeks of marriage but, instead, it occurred either immediately after the birth of their only child or within a few short days;
- That she was the mother of Mr. John MacKenzie's eldest son, George, and not Katherine Gordon, as asserted by Mr. Dickson.
The baptismal entry within the Edinburgh OPR for 15 December 1685 in itself, sufficiently proves points 1 & 3;
There is no evidence to prove Mr. John Mackenzie's subsequent marriage to Katherine Gordon, and the oft-repeated assertion that he married after the death of that first wife to Katherine, daughter of Sir Robert Gordon, is proved incorrect by that Katherine Gordon marrying in 1648, to Major David Barclay of Ury and dying in March 1663, when MacKenzie was but a lad of eight.
Of the son, George, little has been said, however, having been a Jacobite during the '15, he fled to the continent and in August 1722, reports circulated of his having returned to Scotland and being captured. Whether true or not, he was at peace with the Crown and lived for some time at Kensington where he died on 27 July 1760.