Can you share your reference?
The geni profile has:
By a daughter of Dundas of Dundas he had two sons—Sir James Livingstone of Callendar, and Alexander, ancestor of the Livingstones of Dunipace—and two daughters, Janet, married to Sir James Hamilton of Cadzow, and Elizabeth to James Dundas of Dundas.
[Auchinleck Chron.; Histories of Boece, Major, and Lindsay of Pitscottie; Exchequer Rolls of Scotland, vol. iii.; Cal. Documents relating to Scotland, vol. iv.; Douglas's Scottish Peerage (Wood), ii. 124.]
From: https://en.wikisource.org/wiki/Livingstone,_Alexander_(d.1450%3F)_(...