I am just discoering today more research about this couple's lineage and its eventual descent to my earliest Alexander Frazier 1660-1685.
This Alexander Frazier married Catherine Glendining (b. 8 Nov 1659 according to the Old Parochial Registers for Edinburgh Parish 1595-1860 for the Church of Scotland. Catherine was a daughter of George Glendining who married Eupham Nesbit 20 Dec 1649.
This George Glendining was of "The House of Glendonwyn" and he was the youngest son of William Glendining. In the same Edinburgh Parish registers are the exact birth records for George and Eupham's other 6 children also. Their first child was Susanna Glendining b. 24 Jun 1652 and their last was George Glendining b. 3 Feb 1663. Eupham Nesbit b. 17 Dec 1622 Edinburg Parish, Midlothian, Edinburg, scotland and George Glendining's families married into the families of Wauche, Grierson eventually going back to the Lords or Baronets of Lag, Maxwell, and Kennedy families.
Good luck. If you can find Joyce Parson's GREER lineage on freepages.genealogy.rootsweb.ancestry.com/~jandjroots/GREER/d1/g0000009.htm it is very helpful in linking the Wauche & Grierson lines. Also check with Sharon Bryant@cox.net. The Peerage.com has info on Sir John Grierson, 6th Baronet of Lag who is from this ancestral line. Sinerely still digging, Diana Igo