Geddes Mackenzie Simpson was father of Wemyss Mackenzie Simpson (1824-1894) and Frances Ramsay Simpson and both uncle and father-in-law of George Simpson (d. 1860), a governor of the Hudson's Bay Company who began his commercial career in Geddes Mackenzie Simpson's brokerage.
Dictionary of Canadian Biography online John S. Galbraith, Simpson, Sir George, governor of the HNC, author and businessman'; ibid Sylvia van Kirk,'Simpson, Frances Ramsay (Simpson, Lady Simpson), diarist.'