Original sentence: If that were to happen, the Churchill titles would pass to the Duke of Bedford as heir-male of Diana Russell, Duchess of Bedford, a sister of the third Duke of Marlborough.Should Diana's male issue go extinct, the next in line is the Earl of Jersey, the heir-male of Anne Villiers, Countess of Jersey, daughter of Elizabeth Egerton, Duchess of Bridgwater, a younger daughter of the first Duke
Edited sentence: If that were to happen, the Churchill titles would pass to the Earl of Jersey, the heir-male of Anne Villiers, Countess of Jersey, daughter of Elizabeth Egerton, Duchess of Bridgwater, a younger daughter of the first Duke