When they were little children, Princes William and Harry had no idea how unusual the lives ahead of them were going to be.
Their mum Princess Diana wanted them to learn about 'normal' life, taking them on the bus and buying treat McDonald's dinners.
In fact, a royal expert claims William had absolutely no idea he was any different from any other children until he started school.
And it was when he was there that he found out he would one day take the throne - in a truly heartbreaking way.
In his book William and Catherine: Their Lives, Their Wedding, Andrew Morton claims that the little prince realised who he was when his school pals started treating him differently.
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He writes: "Before William attended school, he genuinely had no idea that he was any different from anyone else.
"His innocence of his position was soon ended by fellow pupils, who left him in no doubt who he was.
"On one occasion a classmate reportedly asked him: 'Don’t you know the Queen?'
"William looked at him and replied: ‘Don’t you mean Granny?'"
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William and wife Kate reportedly also decided to keep the truth from Prince George for the first few years of his life.
The dad-of-three has said on several occasions how normal they are behind closed doors.
Speaking in a previous interview, William said: "There'll be a time and a place to bring George up and understand how he fits in, in the world.
"We are very normal."
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Catherine Mayer, who wrote the book Charles: The Heart of a King, said explained how much Prince William struggled with the weight of his future when he was growing up.
Speaking to E! News back in 2015, she said: "With George they are trying to delay that moment of realisation and give him normality before they thrust this on him.
"But it will be, nevertheless, part of his upbringing both in terms of what he sees his parents and grandparents doing and probably quite soon a beginning of an understanding that he is in public life and what that means."
However we imagine he knows now as his school friends have nicknamed him PG - short for Prince George.
