The Queen’s cousin was more widely known in her professional capacity as Lady Elizabeth Anson.
She died in the early hours of Sunday morning with members of her family at her bedside.
Lady Elizabeth was a close friend of the Queen and responsible for arranging many of her private parties.
She was born in Windsor Castle in 1941.
Lady Elizabeth was the daughter of Thomas Anson, Viscount Anson, and his wife, Anne Bowes-Lyon, who would later become Princess Anne of Denmark when she remarried.
She founded the firm Party Planners in 1960.
Lady Elizabeth went on to arrange events for a number of people in the royal houses as well as the Queen.
She leaves one daughter and two grandchildren.
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