He had married
Elizabeth Cromwell, 8th Baroness Cromwell, the daughter and heiress of
Vere Essex Cromwell, 4th Earl of Ardglass and Catherine Hamilton. Before her death in 1709, they were the parents of: •
Edward Southwell (1705–1755), who married Lady Katherine Watson, a daughter of
Edward Watson, Viscount Sondes and Lady Katherine ( Tufton), in 1729. In 1712 he commissioned Sir
John Vanbrugh to build
Kings Weston House in Kingsweston, Bristol. After the death of his first wife, he married Anne Blathwayt (1691–1717), daughter of
William Blathwayt of
Dyrham Park, Gloucestershire, in 1716. Sadly, she died the following year. He died in 1730 and was buried at Kingsweston. His son
Edward from his first marriage, succeeded in turn to the Secretaryship and to the Kings Weston estate.
Descendants Through his son Edward, he was a grandfather of
Edward Southwell, who later became the 20th
Baron de Clifford. ==Works==