[1][2] Following his father's sudden death in 1778, McDonald received "Glengarry" which consisted of 466 acres (1.89 km2) in addition to two houses and lots in Winchester.

[3][7][8] Mary McGuire's maternal grandfather was French architect Samuel D'Obee, charged by Thomas Jefferson with supervising the construction of the Virginia State Capitol in Richmond.

[10] In March 1809, McDonald's wife Mary died and she was interred beside her father, Edward McGuire, in the Old Catholic Churchyard in Winchester.

[13] On June 24, 1814, McDonald received a commission to the rank of captain in the 12th Infantry Regiment following a nomination and appointment by United States President James Madison on February 1 of that year.

[1][3][12] On October 14, 1814, McDonald died in a military hospital in Batavia, New York from health complications caused by a "very long and trying" forced march.