John Dalgleish Donaldson was born on 5 September 1941 in
Cockenzie and Port Seton,
East Lothian,
Scotland, the son of Captain Peter Donaldson and his wife, Mary Dalgleish. Captain Donaldson had sailed regularly from Port Seton Harbour, then in 1962 it is recorded the vessel
Shearwater navigating the
Bass Strait Islands with a cargo of livestock under his command was lost off
Ninth Island. He and his crew were saved and there are still remains of the ship on the island today. On 31 August 1963, Donaldson married his first wife, Henrietta Clark Horne (1942–1997), at Port Seton. They emigrated to
Tasmania, Australia, in November of that year. Donaldson's parents, his elder brother and younger sister also emigrated to Tasmania. His father then joined a large
maritime trading company as a
captain. They had four children, including
Mary Elizabeth Donaldson, who married
King Frederik X (then Crown Prince Frederik) in 2004. In addition to
British citizenship, Donaldson obtained Australian citizenship in 1975. Henrietta died on 20 November 1997, and Donaldson later married
Susan Elizabeth Horwood (born 1940) on 5 September 2001. She is a
novelist who writes under the names Susan Moody, Susannah James and Susan Madison. Donaldson died in
Hobart on 11 April 2026, aged 84. ==Education==