Queen Elizabeth may have wowed in her surprise cameo at Friday's Olympic opening ceremony, but the 86-year-old isn't the only royal to make a splash at London's 2012 Olympic Games.

On Sunday, the Queen's granddaughter, Zara Phillips, made her debut at the Games -- on horseback -- to compete in the Dressage portion of the Games' three-day equestrian competition.

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As her grandfather, the Duke of Edinburgh, and her mother, Princess Anne, looked on, the 31-year-old equestrian guided her horse, High Kingdom, through the course, finishing with a respectable 48.10 penalty points. Phillips' animal made a slight error during his first "flying change," and did not respond immediately to the royal's cues.

"It was disappointing about his first change, but his other ones were really good," Phillips said after competing. "But he coped with all the crowd and is only getting better."

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Phillips' cousin Prince William and his wife Kate Middleton are expected to cheer on the competitor as she enters the final two days of competition and prepares for Monday's cross country showing -- the most difficult portion of the three-day event.

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On Friday, William and Kate joined Queen Elizabeth in the stands to usher in London's 2012 Games at the opening ceremony. The monarch appeared in a pre-taped skit conceptualized by director Danny Boyle alongside Daniel Craig and others.

This article originally appeared on Usmagazine.com: Royal Zara Phillips Makes 2012 London Olympics Debut