Video report by Ciaran Fitzpatrick
70 years ago, Alan Shaw from Bromley was a young soldier on his national service. It was his job to guard Buckingham Palace.
He's one of very few people that can say his shift began serving the King, and ended serving the Queen.
This was because he was on guard when the news of King George VI's death was announced. He experienced firsthand what it was like where power transferred from King to Queen.
There was a unique moment where they mounted King's Guard, and dismounted Queen's Guard.
Also confusion set amongst his team as they couldn't locate black armbands until he was told a while later that only officers wear black armbands.
Now, following the death of Queen Elizabeth II on 8 September, he's looking back to those moments and wondering what those soldiers doing his former job would be thinking.
Alan says, "I think they were more or less be thinking, 'oh, it is unique, will this happen again?' And no, it won't. So not for a long, long time."
"So I think they were proud to have done it. When you think afterwards, like I am now," Alan continues. "I was very proud to have as the Queen in that way."
Alan has met the Queen a couple of times, remarking she was a "marvellous woman" who has done a "fantastic job."
The first time he met her was when she was a Princess and he was 14: "She trod on my foot and turned around and said, 'Oh, I'm sorry!'"
He also says he had "the honour of serving her" at a Dinner Party with Prince Philip.
But his favourite moment was a very unique experience with our new King Charles III.
"One of the guards that was on duty came running along and he said, 'Quick, Charles's rabbit, got out.'
"The guard then said 'I was giving it some lettuce or something and it got out and we were by the police station at the time'.
"And so there was two or three coppers and three guardsman chasing this white rabbit around the lawn of Buckingham Palace."
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