Kate Middleton is proof that blondes have more fun, even if just for a day.

The Princess of Wales reverted back to her signature brunette locks days after stepping out with her new caramel blonde 'do .

She showed off her refreshed look at the Women's Rugby World Cup match between England and Australia at the American Express Stadium in East Sussex, England, Sept. 6, where she cheered from the stands with her usual brown hair pulled back.

Kate, who is the patron of the Rugby Football Union, wore a black blazer over a ruffled white blouse for the spirited occasion.

Two days later, the 43-year-old confirmed that her brunette locks were here to stay when she made a surprise appearance alongside husband Prince William —with whom she shares kids Prince George , 12, Princess

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