Researchers have been working on the lineage of this William Grant:

William GRANT married Catherine GRANT, daughter of Lewis GRANT of Wester Elchies and Ann OGILVIE, in Nov 1769 at Greenburn, Scotland. He was Lieutenant in the 1st Royal Carron Regiment, Carron Parish, Aberlour, Scotland. He fought under General Wolfe at the Battle of the Plains of Abraham in 1759 during the Seven Years War. As a soldier he earned the right to draw land and settle in Canada but he chose to return to Scotland under half-pay. William gave his eldest son Lewis "Power of Attorney" to draw the land to which he, William, was entitled and never claimed. Two of William's sons went to the USA about the same time that Lewis came to Canada. He left a will recorded on 11 May 1804. He died on 13 Jun 1810 at Gladhill, Urquhart, Elgin (will dated 18 May 1803; proved 17 July 1811). He was buried in Scotland.

http://www.sensato.com/Grant/william_grant.htm