"Mary Stewart, Duchess of Richmond and Duchess of Lennox (1622–1685), formerly Lady Mary Villiers, was the daughter of the George Villiers, 1st Duke of Buckingham and Katherine Manners, 19th Baroness de Ros.
On 8 January 1634, at the age of 12, she married the 15-year-old Charles, Lord Herbert, eldest son of the 4th Earl of Pembroke and 1st Earl of Montgomery, but was widowed in 1635 when her young husband died of smallpox or perhaps petechiae. On 3 August 1637, she married the 4th Duke of Lennox, who was created Duke of Richmond in 1641. They had two children:
Esmé Stewart, 2nd Duke of Richmond and 5th Duke of Lennox (2 November 1649 – 10 August 1660), died of smallpox." - (Wikipedia (en) 12.08.2021)
)