Douglas was the eldest son of Sir Archibald Douglas of Glenbervie, Knight, by his spouse Agnes, daughter of William Keith, 3rd Earl Marischal, and upon the death of Archibald Douglas, 8th Earl of Angus without issue, William succeeded to that Earldom as heir-male, in 1588.
He accompanied her in her expedition to the north, and behaved with utmost fortitude and resolution at the fight of Corrichie anno 1562". The earldom was claimed by James VI, who brought a suit against Douglas, for reducing the charters connected with the title, but on 7 March 1589, a decision was given in favour of the latter. He had two charters under The Great Seal of Scotland, from Queen Mary, of the lands and barony of Glenbervie, Kemnay, and several others
Douglas died in July 1591, in his 59th year.
William Douglas, 10th Earl of Angus, eldest son and heir,
Archibald Douglas, Parson of Glenbervie (d1584). George Douglas (d1590)
Sir Robert Douglas of Glenbervie, received from his father the lands of Glenbervie by charter dated 14 July 1592.
Duncan Douglas, Parson of Glenbervie (d1591)
Gavin Douglas (d bef 1 October 1616) who married Elizabeth Keith. Ancestors of the family of Douglas of Bridgeford
Sir John Douglas of Barras
Francis Douglas (dc 1600)
Henry Douglas of Tannachy (d 5 October 1595) who married Janet Murray at sometime before 1580.
Had issue Janet Douglas born 16 April 1580 Dunfermline Scotland.
Margaret Douglas, married William Forbes of Monymusk
Jean Douglas, married John Wishart of Balisycht
Elizabeth Douglas, married Thomas Gordon of Cluny
Sarah Douglas, married 1st Robert Strachan, 2nd George Auchinleck of Balmanno.
