The Prince and Princess of Wales are known to want their children to experience as normal a childhood as they can – which means they kept a big secret from their eldest son, Prince George.

Until about four years ago, George, now aged 11, is believed to have been unaware that he would one day become a monarch – much like his grandfather and one day his father.

The couple made the decision to keep their fate a secret, reportedly telling their son what his future will hold in the summer of 2020.

Royal expert and historian Robert Lacey wrote in his biography Battle of Brothers: “William has not revealed to the world how and when he told his son (George) the big news. Perhaps one day George will tell us the story himself.”

According to Mirrorthe expert said it probably occurred around George’s seventh birthday.

He added: “However, sometime around the boy’s seventh birthday in the summer of 2020, it is believed that his parents went into more detail about what the little prince’s life of future royal ‘service and duty’ would specifically entail.”

Their decision is said to have been linked to “Williams’ unhappiness at the haphazard way in which the whole business of his royal destiny had been buzzing around his head from the start”.

As for Princess Charlotte, nine, and Prince Louis, six, experts have suggested Charlotte may have a similar relationship with her older brother, much like Princess Anne and King Charles.

Writer Katie Nicholl previously spoke to Entertainment Tonight and said: “I think you’re seeing a support act here… William and Kate decided to include Charlotte in it, so in the same way that William always had his wingman in Harry, I I think it’s pretty wonderful that it’s repeated here with George and Charlotte. You’re going to see, I think, real teamwork here.”