Princess Charlotteis one of her dad’s biggest supporters — but it’s not going to hold back her silly side!

On Sunday — one day after being in the saddle to help his grandmotherQueen Elizabeth, 92, celebrate her birthday at Trooping the Colour —Prince Williamwas on horseback of a different kind, playing his favorite summer sport, polo.

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While on the sidelines, Charlotte got into the spirit of the afternoon as she practiced her headstands and put on a pair of very cool sunglasses, much to the enjoyment of her mom.

She was also spotted running around the field with her older brother.

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Also present wasSavannah Phillips, the 7-year-old daughter ofPeter Phillips, who is William’s first cousin and brother ofZara Tindall.

On Saturday, Savannah was the breakout star of Trooping the Colour when sheput her hand over her cousin George’s mouthas he gaped at the flypast.

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Sunday’s game, the Maserati Royal Charity Polo Trophy at Beaufort Polo Club, was to raise funds for theRoyal Marsdencancer hospital and homelessness charityCentrepoint. William is a patron of both.

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William and his brother,Prince Harry, 33, are taking part in a series of games through the coming weeks, bringing in much-needed money for their key charities in the process. The princes have raised more than $14 million for good causes since 2007, their office at Kensington Palace says.

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William’s polo game completed something of a sporty few days for the prince. He indulged his love of motorbikes at the Isle of Man TT races festival on Wednesday — wherehe watched races, met safety workers and sat on a super-bike — and on Thursday met up with the England soccer squad before they head to the World Cup in Russia.

source: people.com