The Duchess of Cambridge - who took along dog Lupo to the event at Coworth Park, near Ascot - accessorised her petal-print Libélula frock with a pair of tan wedges.
Wills, 29, and Harry, 27, showed off their skills on horseback at the annual Audi Polo Challenge while Kate caught up with friends and bonded with her puppy.
Prince Harry also seemed fond of Lupo, taking time out of his sporting activities to affectionately nuzzle the pet.
On Friday Kate, 30, upped the glamour at an Olympics black tie event in a stunning green Jenny Packham gown.
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Esme Riley
