Henrietta 's nephew is Charles Spencer , who is the third son of her sister Anne , and inherited the Marlborough titles .
When Henrietta died in 1733 , the Marlborough titles passed to her nephew Charles Spencer ( 1706–1758 ) , the third son of Henrietta 's late sister Anne ( 1683-1716 ) , who had married the 3rd Earl of Sunderland in 1699 .
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