Prince George Steals Show at Queen Elizabeth II's Birthday Celebration

LONDON— -- It was a grand affair for Queen Elizabeth II today as the royal family gathered to mark "Trooping the Colour," an annual tradition celebrating the queen’s official birthday.

But on this occasion, all eyes were on Prince George, who made his very first balcony appearance, just like his father did at the same age more than 30 years ago.

“It's a very big day for Prince George,” said ABC News’ royal contributor Victoria Murphy. “We very rarely get to see him. He makes very few public appearances, so to be here today, to be standing on that balcony, on that iconic balcony, for the very first time … it’s a huge day for him.”

The third-in-line to the throne, who was just shy of his second birthday, excitedly waved to his parents from inside a Buckingham Palace window as they participated in the festivities to honor the queen.

Prince George looked like a natural as he seemingly mastered the royal wave. He appeared unfazed by the tens of thousands of people who had come out to catch a glimpse of their future king.

Queen Elizabeth II's 89th birthday was actually on April 21 but every year the event takes place on the second Saturday in June when the weather is supposed to be a bit more predictable. She looked regal with Prince Philip, who celebrated his 94th birthday on Wednesday.

Princess Kate, who was decked out in a Catherine Walker coat dress while riding alongside Prince Harry and Camilla, the Duchess of Cornwall, made her first since appearance giving birth to Princess Charlotte about six weeks ago.

"I think that tells us really just how important being here today is for her,” said Murphy. “However, this is a one-off appearance and then she is going to go back to focusing on her family."

Kate took five weeks off after Prince George's birth but is expected to spend most of the summer with her family at their country home in Norfolk about three hours from London while Prince William is busy with his new air ambulance job nearby.

At the family's country home, Kate can spend time with her two children, as her son Prince George has begun picking up another important role: protective big brother. His mother recently took photos of George getting to know his baby sister Charlotte.

Meanwhile, Princess Charlotte wasn't expected to attend Trooping the Colour today.

"Princess Charlotte is just a little too young to be making her first balcony appearance just yet," said Murphy.

The royal family typically waits until the children are two years old before they make their first balcony appearance.

In about three short weeks, the royal family will gather again for another milestone: Princess Charlotte's christening at Mary Magdalene Church on the queen’s estate in Sandringham. However, it will be a much more intimate affair -- Prince George's christening was just 22 people: the queen and Prince Philip; Prince Charles and Camilla; Prince Harry; Kate’s family; and, George’s godparents.

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