Her father was said to been a son of Robert Hampden-Trevor, 1st Viscount Hampden, by a Fleet Marriage, the validity of which was not admitted.
[4] He was born 13 Aug 1740; admitted to Westminster School in October 1752; Edinburgh University.
His first wife died in 1771 and he later remarried; John Trevor became Chaplain to the 4th (and last) Earl of Deloraine in 1776.
He moved to the Continent and became Chaplain to Company of Merchant Adventurers, Hamburg Apr 1779 - Jun 1780; He was awarded a Doctor of Divinity degree on 15 Oct 1779.
Frances was educated at a Roman Catholic Convent, and left at 17 years of age, just before she met her husband[5]