The Queen has already passed the record of the longest-serving British monarch, but her marriage has endured even longer
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Queen Elizabeth may have passed the record as the longest-reigning British monarch, but she has been counting on the support of her mainstay Prince Philip even longer.

They wed on November 20, 1947, at Westminster Abbey (just like Prince William and the then-Kate Middleton in 2011) after a year-long courtship. But their friendship had been going on far longer, with those who know her saying Elizabeth knew Philip was the man for her from as early as age 13.

“She saw in him a freshness. He’s very bright, he’s complex and she knew he might not be easy, but he wouldn’t be boring,” Sally Bedell Smith, author of Elizabeth the Queen: The Life of a Modern Monarch, tells PEOPLE. “Someone who works with them has said, ‘She lights up when he walks into the room.’ She becomes softer and lighter and happier.”

Many observers say the first signal that the two were destined for a future together came when a picture emerged of them at the wedding of their mutual cousin, Lady Patricia Mountbatten, in October 1946. They were spotted in the doorway of the Romsey Abbey in Hampshire, and as Elizabeth removed her coat, Philip looked on smiling, with his eyes locked on hers.

Queen Elizabeth
The then Princess Elizabeth and Prince Philip on their wedding day
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While he was a handsome prince five years her senior, Elizabeth was a fresh-faced beauty. “Patricia Mountbatten said, ‘She has such beautiful skin,’ ” Bedell Smith adds. “And Philip said, ‘She’s like that all over.’ There was a physical attraction!”

The Queen, 94, loves musicals – and one tune from Oklahoma is said to be the couple’s “song.” “One of her favorite songs, which she and Prince Phillip used to dance to when they were engaged, is ‘People Will Say We’re In Love,’ ” says Ingrid Seward, author of The Queen’s Speech. “She loves all the musicals.”

In later years, their bond has been more obvious at country sporting shows, where the Queen has been pictured dashing between racing courses as she enthusiastically watches her husband compete in carriage-driving contests.

Royalty - Princess Elizabeth and Duke of Edinburgh with Prince Charles - Buckingham Palace, London
Prince Philip, Prince Charles and Queen Elizabeth
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Normally, it is Philip, 99, who has to follow his wife. He gave up a promising Naval career for a lifetime of devoted service – always a couple of steps behind her, as dictated by royal protocol.

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“He’s said that supporting the Queen has defined his life,” says Bedell Smith. “Certainly his personality has provided some relief to her in the midst of their official duties.”