Following the death of their father in 1717 the title was initially held by the eldest brother, Richard, until he died without a male heir in 1738.
It then passed to the second son, Caryll, who also died in 1745 leaving the title to William.
[1] As a priest in charge of a Catholic mission at Scholes near Prescot, he handed control of the estates to his younger brother Thomas on the grounds that he was "old and had no intention to marry".
[2] He died on 30 March 1759 and the title passed to Thomas' son, Charles.
[3][4] Other accounts state that the 7th viscount was Richard (born c1700) the son of Richard (5th viscount) and who was a Catholic priest in New England for a time as head of the Jesuits there and that the title then passed to William, also a Catholic priest.