Prince William: Polo with Harry After Registering George's Birth!

Prince William shows off his toned arms while playing polo at Coworth Polo Club on Saturday (August 3) in Ascot, England.

The 31-year-old royal was joined by his younger brother Prince Harry.

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This was the first time that William has been spotted since the birth of his baby boy George Alexander Louis last week.

The day before, Harry saluted the troops while visiting Royal Marines Tamar, HM Naval Base in London.

On the same day, William and his wife Kate Middleton registered the birth of Prince George.

“The Duke and Duchess of Cambridge have formally registered the birth of Prince George,” Kensington Palace said in a statement. “The Duke of Cambridge signed the birth register at Kensington Palace this morning, witnessed by a Registrar from Westminster Register Office.”