Career
They had six children:
Lady Mary Catherine Bertie (14 April 1754 – 12 April 1767)
Peregrine Thomas Bertie, Marquess of Lindsey (21 May 1755 – 12 December 1758)
a son (born and died 14 September 1759)
Robert Bertie, 4th Duke of Ancaster and Kesteven (1756–1779)
Priscilla Barbara Elizabeth Bertie, Baroness Willoughby de Eresby (16 February 1761 – 29 December 1828)
Lady Georgina Charlotte Bertie (7 August 1761 – 1838), married George Cholmondeley, 1st Marquess of Cholmondeley and had issue. On the death of his father in 1742, he succeeded him in the dukedom and as Lord Great Chamberlain and Lord Lieutenant of Lincolnshire, and was appointed to the Privy Council. He gained the rank of Major-General on 19 January 1755, Lieutenant-General on 3 February 1759 and General on 25 May 1772.