[3] In 1909 he married Hilda Mary Gardiner, a dancer and mime artist, and follower of the actor Edward Gordon Craig.
In the year of 1923 he bought Dunshay Manor in the hills of the Isle of Purbeck, after already having spent holidays in nearby Swanage.
He died in London at age 65 and a memorial exhibition was held at the Fine Art Society in the same year.
Born in London, Watson studied at the Royal Academy from 1889; he exhibited there from 1891 and also at the Paris salon.
Retrospective exhibitions were held at the Galerie Heinemann, Munich in 1912, and at the Fine Art Society in 1914.