Francis was believed to hold the Barony de Clifford, created in 1299, which could therefore be used to give Henry a seat in the House of Lords during his father's lifetime via a writ of acceleration.
The younger Boyle inherited his father's titles in 1643, but was unable to sit in the English House of Lords as they were all in the Peerage of Ireland.
In 1644 he was therefore created Baron Clifford of Lanesborough in the Peerage of England, which allowed him to sit in the Lords.
The 1628 Clifford barony then devolved upon Charlotte Cavendish, Marchioness of Hartington, wife of the future 4th Duke of Devonshire.
Current co-heirs to the barony are George Howard, 13th Earl of Carlisle (heir of the 8th baron's sister Georgiana) and Fergus Leveson-Gower, 6th Earl Granville (heir of the 8th baron's sister Harriet).