On 19 January 1511, he married Lady Elizabeth Stewart, daughter of
John Stewart, 1st Earl of Atholl, and Lady Eleanor Sinclair, daughter of
William Sinclair, 3rd Earl of Orkney. Their children included: •
Matthew Stewart, 4th Earl of Lennox. •
Robert Stewart, 1st Earl of March. • John Stewart, 5th Lord of Aubigny (died c. 1567), father of
Esmé Stewart, 1st Duke of Lennox. • Lady Helen (or Eleanor) Stewart, who married: firstly, to
William Hay, 6th Earl of Erroll; secondly, to
John Gordon, 11th Earl of Sutherland. She died in the 1560s. • Lady Janet Stewart, who married
Ninian Ross. She was the mistress of King
James V, and the mother of Adam Stewart, Prior of
Perth Charterhouse. In March 1539, Helen Stewart and Elizabeth Stewart were with the household of
Mary of Guise at
Linlithgow Palace. The king's tailor
Thomas Arthur made gowns and kirtles for them of black velvet, satin, and taffeta, with French hats and riding hoods. In 2026, the
Daily Mail asserted that Stewart is the common ancestor of
Charles III and
Donald Trump, making them 15th cousins. ==Ancestors==