When the Prince of Wales graduated from the University of St Andrews in June 2005, he was cheered on by members of the royal family including his father King Charles and his late grandparents, Prince Philip and Queen Elizabeth II.
The royals mingled with other graduates and their loved ones at a garden party after the ceremony and out of all the guests, it was the Queen who overstayed!
Dr Brian Lang, who was Principal and Vice Chancellor of the university during William's time, told HELLO!: "We had a very, very happy day. The sun shone. There was a little garden party. The late Queen way overstayed the time she was supposed to be in St Andrews.
"She met other parents, other grandparents and she made it quite clear to her staff that she was not going to leave until she was ready to. A few days later, I came across the Queen again. I was presented to her at the opening of a new public building in Edinburgh. And she explained what a wonderful time she had had that day in St Andrews.
"I remember her calling out, 'Philip, Philip, come here quickly. It's Dr Lang from St Andrews.' We had such a lovely day."
Dr Lang, who had dealt with the royals in his previous job and was in regular contact with William during his university days, went on to praise the late Queen and the Firm.
"The Queen was wonderful. She was a great lady," he said. "She would be quite reserved when she first meets you, but as soon as she realises that you're actually quite a reasonable human being, her eye begins to twinkle and she loves a funny story.
"I had lunch with the Queen not long afterwards and she again repeated how happy she'd been to have seen William at St Andrews."
"The royals are charming," he added. "They are very comfortable meeting people. They're sociable, very friendly and they put people at their ease very, very quickly."
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