From preschool to the palace, the future king is growing up

Prince George is growing up! Subscribe now for all about the 3-year-old royal s life at home, his preschool adventures and how he s growing into a proper little chap , only in PEOPLE!

Now that he is 3, Prince George is really hitting his stride – one toddler-sized step at a time.

The future king, who celebrated his third birthday with a tea party at home on July 22, is growing in stature and confidence, say those who know him.

“He’s a little boy now,” a close family friend tells PEOPLE in this week’s cover story. “A proper little chap!”

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When he’s not at the family’s London home of Kensington Palace, Princess Charlotte‘s big brother attends preschool three mornings a week at Westacre Montessori near the family’s country home in Norfolk, Anmer Hall.

The airplane-loving boy, who is currently obsessed with anything with wheels, showed off his take-charge personality during a recent visit with dad Prince William and mom Princess Kate to an air show.

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Sitting in the pilot seat of an Australian Air Force plane on July 8, “he thought the laptop we’d left out were the controls,” Corporal Pete Blogg tells PEOPLE, “and he was tapping away, pretending he was flying.”

For much more on Prince George’s life, pick up this week’s issue of PEOPLE, on newsstands Friday