[3] He was educated at Eton School from 1739 to 1743, and matriculated at St John's College, Oxford in 1744.

As Lord Lieutenant he took personal command of the Denbighshire Militia for the first two years after it was reformed in 1760.

On 14 March 1761, he married Elizabeth Rushout (1730–1772), the daughter of Lady Anne Compton (the sixth daughter of George Compton, 4th Earl of Northampton) and Sir John Rushout, 4th Baronet of Northwick Park, Gloucestershire.

Before her death on 7 November 1772, they were the parents of one son and three daughters, including: Myddelton married, secondly, Mary Lloyd, in 1778.

Upon his unmarried son's death the following year on 20 December 1796, Chirk Castle and some local land was inherited by his daughter Charlotte, who had married Robert Biddulph.