A brand new book claims to shed new light on the Queen as she celebrates her Platinum Jubilee and 70 years on the throne.
It is written by prominent royal author Andrew Morton, who is best known for his biography of Princess Diana, and has now turned his attentions to Her Majesty.
Called The Queen, the book's publisher says it "takes you behind the scenes to uncover the woman behind the Crown".
And so far, it has been serialised in the Daily Mail, where Morton examines the relationship between the Queen and Diana, and how the monarch dealt with the princess's untimely death.
Here are seven revelations that have been made in the book's serialisation about the two women...
Queen was at 'wit's end'
According to the book, the Queen was at her "wit's end" as the marriages of two of her sons - Prince Charles and Prince Andrew - crumbled at the same time.
In 1992, both Charles split from Diana while Andrew separated from his then-wife, Sarah Ferguson.
Morton writes: "In the 1990s, her remarkable equilibrium was tested far more than we ever knew.
"According to a friend of hers, she was at her 'wits' end' when both Charles and Andrew's marriages collapsed, wondering aloud when her family, and the monarchy, would finally be given some respite."
Impact of Charles and Diana's split
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Morton adds that the separation of Charles and Diana affected the monarch so deeply that "she allowed herself to stray from the ingrained habits of a lifetime".
He added: "No longer did she have just one dry martini in the evenings; her staff noticed that Her Majesty's modest consumption of alcohol had noticeably increased. "
Queen had called Diana 'one of us' at first
According to the book, Diana impressed the Queen during early meetings with the monarch during her courtship with Charles.
Morton writes that after Diana's first visit to Balmoral in 1980, the Queen remarked: "She's one of us."
Queen was annoyed with Diana and Fergie's antics on Andrew's stag night
Morton's new book also charts Diana's bond with her former sister-in-law Fergie - and writes that how at first, the Queen was pleased with their relationship.
However, he adds that one incident left the Queen annoyed with their pair's behaviour - and it came during Prince Andrew's stag do when the pair dressed as policewomen and intend to 'arrest' the groom before heading out for cocktails.
Morton writes: "Once the story got out, the Monarch was deeply annoyed that the future Queen of England had been spotted roaming around London dressed as a police officer, which was technically a criminal offence. Diana was called in to see her."
Queen and Charles consoled one another after Diana's death
The new book, serialised in the Daily Mail, also examines the Queen's response during one of the most toughest moments of her reign - the death of Princess Diana.
Her Majesty was at Balmoral with Charles and his sons with Diana Prince William and Prince Harry when the terrible news filtered through that she had died following a car crash in Paris.
Upon hearing of Diana's tragic death, the book claims that in a "rare show of affection", the sovereign and her son physically consoled one another, perhaps sensing that this event was going to be emotionally unprecedented".
Morton added: "The Queen ordered a pot of tea but never touched a drop as she, Prince Philip and Prince Charles paced the tartan-carpeted corridor, wondering what should be done."
Queen at first did not welcome Tony Blair's 'People's Princess' description
In the hours after the news of Diana's death broke, tributes to her began flooding in from all over the world.
One tribute in particular that many people remember was from then new-Prime Minister Tony Blair, who called her the "people's princess".
But in Morton's new book, he writes that some observers believe this was "not entirely welcomed by the Queen".
Queen felt 'utterly bewildered' returning to London after Diana's death
In the days after Diana's death, the royals remained at Balmoral and rallied around Diana's grieving sons William and Harry.
Eventually, they made the trip back to London in time for Diana's funeral and the capital was awash with mourners, many of them sobbing.
Morton writes: "As a senior aide explained: 'At Balmoral, she hadn't taken it in. You never know what it is like until you are actually there.
"'All the remarks and people hugging each other, sobbing — the whole nation seemed to have gone bananas. The Queen and Prince Philip felt utterly bewildered.'"
The Queen by Andrew Morton published by Michael O'Mara is available on May 24.
