See Princess Charlotte and Prince George Adorably Cheer on Dad William at Polo!

Princess Charlotte is 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 grandmother Queen Elizabeth, 92, celebrate her birthday at Trooping the Colour — Prince William was on horseback of a different kind, playing his favorite summer sport, polo.

Bringing along his own cheering section, William was joined by his wife Kate Middleton and their children Prince George, 4, and Charlotte, 3. However, there was no sign of the couple’s 6-week-old son Prince Louis.

Princess Charlotte and Kate Middleton
Princess Charlotte and Kate Middleton
Prince George and Kate Middleton
Prince George and Kate Middleton

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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.

Princess Charlotte and Kate Middleton
Princess Charlotte and Kate Middleton
Prince George and Princess Charlotte
Prince George and Princess Charlotte

Also present was Savannah Phillips, the 7-year-old daughter of Peter Phillips, who is William’s first cousin and brother of Zara Tindall.

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

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

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.

Prince William
Prince William
Prince William
Prince William
Prince William and Kate Middleton
Prince William and Kate Middleton

Last month, William played publicly for the first time this season at nearby Cirencester Park, watched by his due-any-day-now cousin Zara Tindall.

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 — where he 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.