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

Prince George made his very first balcony appearance.

“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.”

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.

"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."

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.

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