The guests are arriving at Westminster Abbey, and Us Weekly caught up with famed British couple Elton John and David Furnish as they made their way inside the church.
John, 64 -- who was a dear friend of Prince William's mother, the late Princess Diana -- spoke more in-depth about the couple's union during a recent appearance on Good Morning America.
"The last time we were in Westminster Abbey, my heart sank when I saw those [William and Harry] walking behind the coffin. I thought that was the hardest thing. I can't imagine at that young age, having to walk in public, following your mother's coffin," the singer said. "And the next time we're in the Abbey, it's to see William walking up the aisle with a beautiful woman and the love of his life."
John, who welcomed son Zachary Jackson Levon in December, added that William's mother would have been quite fond of Kate Middleton, 29.
"I think it's the most joyous result and I'm sure Diana would be very, very happy about it," he added. "I think that she would be very happy with his choice. Kate seems like such a great girl, and they seem so much in love."
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