About William Douglas, of Whittingham
Son of Richard Douglas, who was second son of James, second Earl of Morton. He obtained on the 17th August 1560, a charter of the ecclesiastical lands of Whittinghame from Claud Hamilton, then Dean of Dunbar, with consent of the Duke of Chastelherault his father. He joined the Lords of the Congregation and seems to have been frequently employed by the General Assembly in their communications with the queen and privy council. He was engaged with his kinsman, Morton, in the slaughter of Rizzio, but was pardoned on the 24th December 1566. He joined the association for preservation of James VI. in 1567. He was appointed an ordinary senator previous to the 20th October 1575, on which day he is marked in the books of Sederunt as absent; but the book from 1568 to that date being now amissing it is impossible to fix the precise date of his admission. On the 9th January 1579, he was excused attendance, as well as his brother the parson of Glasgow, in respect it was shown that the said Master Archibald has contracted "ane soamess and swelling in his heels, wherethrow the uther bruyther and he remains togidder, quhile God send better fortune to them". He resigned his place previous to the 1st August 1590, on which day his son Archibald was presented to it by the king.
An Historical Account of the Senators of the College of Justice: From Its Institution in MDXXXII; by George Brunton, David Haig; 1832; Page 160.
Note: Wikipedia Entry indicates William to be the eldest son and heir of William Douglas of Whittinghame (died bef. 24 August 1557) and his spouse Elizabeth (d. after 24 August 1557), daughter of Sir Robert Lauder of The Bass (d.1517/18) by his spouse, Elizabeth Lawson.