Her Majesty the Queen was determined to keep her promise to serve her country right up until the very end, despite her declining health.

Just two days before her death, she met the departing Prime Minister, Boris Johnson, and his replacement, Liz Truss at Balmoral. She had initially intended to travel from Scotland to London for the meetings, but her frailty meant this was simply not possible. Instead, she was pictured in the Drawing Room at Balmoral on 6 September, beaming as she waited to greet the politicians.

According to royal author Robert Hardman, the logistics of the meetings with Mr Johnson and Ms Truss were planned by her private secretary Sir Edward Young, Palace doctors and the Cabinet Secretary, Simon Case, who timed it so that the Queen would meet with both in the same hour at lunchtime. Mr Johnson later said of the meeting: “Given how ill she obviously was, how amazing it was that she be so bright and focused.” Ms Truss further noted: “She stood up to greet me. She was clearly physically not very well but we talked for about 20 minutes. She was alert.”

Hardman revealed in his book, Charles III: New King, New Court. The Inside Story, that following the meeting, the Queen watched her horse, Love Affairs, win at Goodwood Racecourse in West Sussex at 3.05pm later that afternoon. And despite it being a busy day for the 96-year-old monarch, she was in good spirits, described as being ‘quite buzzy over pre-dinner drinks’. But she decided to have dinner alone and went upstairs.

On the morning of September 7, her health took a turn for the worse. She spent the day in bed, but in an act of dedication to her duty, still wished to appear at that evening’s Privy Council meeting over video. As such, provisions were put in place so she could be audio-only if she stayed in her bedroom. However, moments before the meeting was due to begin, the Queen cancelled on the grounds of ‘medical advice’, as was reported at the time.

Penny Mordaunt, who had been appointed as Lord President of the Council, said of her commitment: “For me, that was testament to the depth of [the Queen’s] devotion to her duty and us: the day before she passed, she was still trying to fulfil her ­obligations as sovereign, which I find incredible.” That same evening, on 7 September, Charles was advised by his sister Princess Anne and his private secretary to make his way to the Queen’s bedside ASAP.

By chance, both Charles and Anne were in Scotland at the time, having carried out events in the country earlier in the week. It meant they got to spend time with their beloved mother before she peacefully passed away. Charles was informed of the Queen’s death via telephone. He had briefly stepped away from her bedside to clear his head and had gone out to gather mushrooms. He received the news that she had died as he was driving back to Balmoral when his most senior aide took a call. Charles pulled over and was addressed for the first time as ‘Your Majesty’ – signalling he was now King, Hardman wrote.