[4] Watts, one of the most prominent and wealthy landowners in the colonies and was one of the original subscribers to the Tontine Coffee House.

In 1779, his properties, including his "Rose Hill" estate (which today is occupied by Fordham University), were seized by the New York State Legislature.

Together, they were the parents of:[8] Watts died in Wales on August 15, 1789, and was buried in St James's Church, Piccadilly, London.

[7] Through their children, the Watts became ancestors of the Marquess of Ailsa in Scotland, the Duke of Grafton and the Viscount Daventry in England.

[12] Through his daughter Susanna, he was the grandfather of Major General Stephen Watts Kearny (1794–1848) and great-grandfather of Gen. Philip Kearny (1815–1862), a United States Army officer notable for his leadership in the Mexican–American War and American Civil War who was killed in action in the 1862 Battle of Chantilly.