He was the son of Lieutenant George Burnet, a soldier in the Kirkcudbright and Galloway Militia, and Margaret Wardlaw, who was the daughter of a Dalkeith merchant, John Wardlaw.
He was the offspring of Lieutenant George Burnet, a soldier in the Kirkcudbright and Galloway Militia, and Margaret Wardlaw, whose father was a Dalkeith merchant, John Wardlaw.