Queen Elizabeth Realized She Was 'Not Going to Reach 100' Like Her Mother, Says Biographer

Royal biographer Robert Hardman writes that the late Queen was intentional about how she spent her final year

Queen Elizabeth was aware that the clock was ticking during her final year, royal biographer Robert Hardman writes in his new book on King Charles.

Queen Elizabeth died on Sept. 8, 2022, at age 96 during the 70th year of her record-breaking reign, and Hardman sheds new light on details around her death in The Making of a King: King Charles III and the Modern Monarchy (out Jan. 18).

In an excerpt of his book in the Daily Mail on Saturday, Hardman writes that the Queen’s exact cause of death is unclear because she had been “suffering from multiple conditions in her final year.” (Biographer Gyles Brandreth previously reported that the Queen had myeloma, a bone marrow cancer and that the palace refused to comment.)

“‘She had come to realize that the medical prognosis meant she was not going to emulate her mother and reach one hundred [the Queen Mother died at age 101 in 2002], so she had been determined to make the most of that year,’ ” Hardman quotes a friend as saying in The Making of The King. “‘She made sure she had all the family over the summer, so that the young ones in particular would always be left with happy memories of her.’ ”

Related: Queen Elizabeth Knew Her Time Was Running Short, 'Had No Regrets' Before Her Death, Book Says

Due to the Queen's advanced age, serious thought had been given to the possibility of a regency, which would allow Charles to stand in for her if she was deemed physically or mentally unable.

'With the Queen Mother going on past her 100th birthday, of course we had to think that the Queen would reach the same age. A regency seemed almost inevitable. That would have been very difficult,' says a senior former aide, according to the excerpt.

However, Charles was reluctant to discuss the matter at length.

'You could turn up with all the papers and he would say, 'Have you been through it all? Are you happy with this?' and that would be that,' an aide says in Daily Mail's excerpt. 'He didn't want to dwell on the details… I think he felt that if you reach out for something, you are tempting fate.'

Queen Elizabeth also spoke to her family about where she might spend her final days, Hardman says.

“Right to the end, she was endearingly conscious of causing unnecessary inconvenience to others,” he writes, according to the excerpt.

Hardman mentions Princess Anne’s comments about those conversations, referring to the remarks she made in the BBC One documentary Charles III: The Coronation Year.

“There was a moment when she felt that it would be more difficult if she died at Balmoral,” the Princess Royal said in the special, which premiered on Boxing Day (the day after Christmas) in the U.K. “I think we did try and persuade her that shouldn’t be part of the decision-making process. So I hope she felt that that was right in the end,” Princess Anne said.

Related: Princess Anne Says Queen Elizabeth Worried Dying at Balmoral Would Make Things 'Difficult'

Sources told PEOPLE at the time of the late Queen’s death that it had been fitting that she spend her last hours at Balmoral because it was such a special place for her and her family.

On what would have been Queen Elizabeth’s 97th birthday in April 2023, Prince William and Kate Middleton released a never-before-seen picture of the matriarch at her beloved home in the Scottish Highlands. The photo showed the Queen with some of her grandchildren and great-grandchildren, and was taken by Kate.

"Today would have been Her Late Majesty Queen Elizabeth's 97th birthday," the caption read. "This photograph — showing her with some of her grandchildren and great-grandchildren — was taken at Balmoral last summer."

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The photo showed the Queen seated on a couch surrounded by the next generations of royals, including Prince George, 10, and Princess Charlotte, 8, and Prince Louis, 5.

Zara and Mike Tindall’s three kids Mia, 9, Lena, 5, and Lucas, 2, also smiled for the shot, as did Peter Phillips’ daughters Savannah, 13, and Isla, 11. The Queen’s two youngest grandchildren Lady Louise Windsor, 20, and James, Earl of Wessex, 16, the children of Prince Edward and Sophie, the Duchess of Edinburgh, stood behind their younger cousins. 

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