Five-year-oldPrince Georgeis coming into his own.

George is “very independent now and not as interested in playing with Charlotte all the time,” a source tells PEOPLE in this week’s issue. “They are close, but George likes to go off and do his own thing.”

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Maserati Royal Charity Polo Trophy

Maserati Royal Charity Polo Trophy

You wouldn’t be able to tell from hissmiling fifth birthday portrait, butPrince Georgehas also been showing off his shy side recently.

However, George is a talkative little prince once he gets to know someone. “George takes a little while to warm up, but once he’s comfortable with you, he’s very chatty and charming,” says the insider.

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prince-george

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George showed off both sides of his personality on his first day of school at Thomas’s Battersea in September. He posed for an official picture with his dad,Prince William, at home at Kensington Palace before leaving for the big day in which the father and son (in his perfectly pressed uniform!) held hands with big smiles on their faces.

Upon exiting the family’s Range Rover when he arrived at school, George looked very serious (and a bit nervous!) as he greeted and shook hands with the head of Thomas’s lower school, Helen Haslem.

However, the source says the third heir in line to the throne is “very happy” at his new school, where he is known as George Cambridge.

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Prince George Attends Thomas’s Battersea On His First Day At School

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“George ran with his head up as fast as he could,” says an observer. “He looked back at Charlotte once or twice but kept on going. He was not holding back. And the first thing he did when he got there was slide down the hill on his bum.”

Mom Kate pointed out a group of photographers to the children as a gentle reminder, but “she let them get on with it, sliding and rolling on the grass. They were loving the great big area to play in on such a sunny day.”

source: people.com