A source (who has closely watched Prince George grow up) told Fabulous that the youngster has a strong sense of responsibility and is "very much his own man."
“With younger siblings Charlotte and Louis taking a lot of the attention at home, George is learning to be more independent," the source added.
While Prince George appears to have a playful side, and Prince William has implied that his son can be "a handful," he is naturally shyer and more serious than his sister Charlotte.
WATCH: Prince George bursts into tears after being yelled at by Kate Middleton
According to News.com, sources close to George claim that although he seems reserved, the young royal is chatty and open when he is comfortable with the company.
“George likes people...whether he has learned this from his father or it simply comes naturally, he first likes to be sure that he can trust them," the source said, adding, “Growing up surrounded by courtiers, you learn fast that not everybody has your best interests at heart."
It's no surprise then, that his birthday celebrations thus far have involved a family-only trip to the Carribean Island of Mustique.