It was at this time that Sarah, Dowager Duchess of Marlborough, arranged Lady Mary's marriage to Thomas Osborne, 4th Duke of Leeds; they were married on 26 June 1740.
To bylo v době, kdy Sarah, vévodkyně vdova z Marlborough, sjednala Maryin sňatek s Thomasem Osbornem, 4. vévodou z Leeds; svatba se konala 26. června 1740.