Most 8-year-olds see life moment by moment: When is the next play date? But for one eight-year-old in the United Kingdom, the third in line to the British throne, everything in his life is planned out for him. So where do parents begin when telling a little boy his big destiny?

For the Duke and Duchess of Cambridge, parents of 8-year-old future King George, the plan to tell George his future was very deliberate.

And he only found out around his seventh birthday in July 2020, says royal historian and biographer Robert Lacey, author of Battle of Brothers: Battle of Brothers: William and Harry-The Inside Story of a Family in Tumult (opens in new tab), says royal historian and biographer Robert Lacey, author of Battle of Brothers: William and Harry-The Inside Story of a Family in Tumult. This age was specifically chosen as "the controlled moment they chose," he says.

"William has not revealed to the world how or when he broke the big news to his son," Lacey says. 'Maybe one day George will tell us himself. But it is believed that by the time the boy celebrates his seventh birthday in the summer of 2020, his parents will have explained in greater detail what this little prince's future life of "service and duty" will be like in particular."

This collaborative approach was in stark contrast to the way William himself knew he would one day become king, "William was frustrated," says Lacey, "by the haphazard way in which the whole business of royal destiny had hovered around his head from the beginning.

Nevertheless, one of the cornerstones of the royal education that William enjoyed was being taught what it took to be a monarch by someone who knew it well. His grandmother, the Queen, was a regular visitor to Windsor Castle while William was a student at nearby Eton College.

"As a student at Eton College, young Prince William walked up the hill and came for tea with the Queen at Windsor Castle, learning how to prepare himself for his future as king," the Mirror reported.

William has said many times how much his grandmother's influence meant to him growing up.

"There has always been a special intimacy between William and the queen, and the queen takes a special interest in William," says Lacey. When William became a teenager, "the Queen took him to Windsor Castle, opened the state boxes, and showed him the papers. That was William's constitutional education."

He seems to have taken notes from that education and hopes to pass on his royal knowledge to his successor.

"It was especially important for me to have someone like the Queen to look up to, to be there, to understand the complexities of losing a loved one," William told Sky News in 2016, before Her Majesty the Queen turned 90. 'So she was incredibly supportive and I really appreciated her guidance.'