sentences:  The marriage also upset Anglo-Scottish diplomacy, as the possibility of a union between Lady Katherine and the Earl of Arran, a young and unstable nobleman with a strong claim to the Scottish throne, had thereby been removed as an option.The Queen also disapproved of her choice of husband and, still unmarried, also feared that Katherine's ability to bear male offspring could possibly facilitate a rebellion in support of Katherine as queen.To Katherine's misfortune, her claim to the throne was at the time argued by a book written by John Hales.