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Although she retains her title, the Duchess of York has remained on the periphery of the Royal Family following the scandals that have dogged her life.
Over the past decade, Kate has transformed her style from university student to Duchess, with the utterly elegant, chic and classic look we know and love today.
It is impossible to ignore Diana, Princess of Wales's impact on the world of fashion. She became one of the world's most enduring style icons, and her looks were - and still are - so famous they come with stories of their own.
Although she may not be thought of as a trend-setter or trailblazer in the fashion world, if asked to define style - the Queen is the perfect example.