Clare Hazell became the Countess of Iveagh when she married Edward Guinness, 4th Earl of Iveagh and heir to the Guinness brewery fortune.

Rachel Chandler married Tom Guinness who is the son of Jonathan Guinness, 3rd Baron Moyne, also heir to the Guinness brewery $$

Edward Guinness, 1st Earl of Iveagh is the great grandfather of Jonathan & Edward so that would make Tom 3rd cousin once-removed to Jonathan.

Kind of wonder what else is involved in the Guinness family.

FWIW, Jonathan's mother was socialite Diana Mitford & his stepfather was noted British Nazi Sir Oswald Mosley.

https://en.wikipedia.org/wiki/Guinness_family