Princess Anne's 'important relationship' with King Charles shown in two-word nickname

Princess Anne has a cheeky two-word nickname for her brother, King Charles, that highlights the close bond they share. This revelation comes after a candid exchange between the siblings was caught on camera during behind-the-scenes footage from the King's coronation.

The Royal Family were gathered in the Buckingham Palace Centre Room, awaiting their appearance to greet the public. The room reportedly looked like a "building site" at the time due to extensive renovations being carried out as part of a whopping £369m project to refurbish the palace complex.

Robert Hardman, an author whose team was filming the royals as they prepared to step onto the balcony, noted that this brief moment before their public appearance was the first opportunity they had to "chat" all day. The 76-year-old King had been crowned at Westminster Abbey earlier that day, followed by a state procession to Buckingham Palace.

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In the footage, which features in the documentary Charles II: The Coronation Year, Princess Anne is seen entering the Centre Room and greeting her brother with a simple "Hello Old Bean". The King responds with laughter before warmly greeting his sister.

Hardman, the documentary's lead, shared: "There was this sweet moment as the Royal Family were gathering to go out on the balcony for the big wave and the fly past, and actually the palace was a building site at the time, it was the east wing, it was chaos, and everything was held up with bits of tape. There were floorboards covered in chipboard, and everyone was treading carefully to make sure they didn't snag a robe on a stray nail or whatever.

"And then they came into the centreroom, which is the room that comes onto the balcony and it was the first time they had all had the chance to chat after the service. And the Princess comes in, sees the King, and says, 'Hello Old Bean'.

"It's so English but it's that relationship. It's so important for the sovereign to have that sort of [relationship], particularly for a king. King George V was always terribly fond of his sister, it was a very endearing connection."

The King has always been said to have had a close bond with his sister. While Anne is just under two years younger than the monarch, there is more than a decade separating the King and Prince Andrew, with Prince Edward 15 years younger than Charles.

Hannah Furniss, The Telegraph's Royal Editor, discussed Charles and Anne's relationship in a YouTube video of the publication's Royal Insight, stating: "They've grown up together, they spent their childhood together when the Queen and Prince Philip were travelling a lot. They're very close."

She added: "They have this very warm relationship and she is probably in a better position than anyone to give him advice, give him a bit of sympathy when he needs it, give him a bit of a pep talk."

A Royal insider previously revealed to Woman's Day Magazine that Anne serves as the King's "confidante".

They said: "Camilla might be the love of his life, but Anne's his greatest and most reliable confidante.

"Anne's the only one with the ability to tell him uncomfortable truths and pull him back from any emotional distractions."

Former BBC correspondent Wesley Kerr believes the King depends on Anne for "complete discretion". He said: "She is the person The King has known longest...Anne is wise, intelligent, and incredibly plugged into the modern United Kingdom. She understands completely who and what has shaped him and is eager for him to succeed: for the sake of their beloved mum and dad and for country and Commonwealth."