They said: “I’m sure it’ll be a bit of a bittersweet moment.
“This is her son and his wife, so in some ways, it will be coming full circle – but it will also be a poignant reminder of what we all lost.”
William married Kate in 2011 in a ceremony at Westminster Abbey which attracted attention worldwide.
But William once opened up on a disagreement he had with the Queen over what he should wear for the wedding.
She was not keen on his desire to wear a frock coat he had adorned in previous royal engagements.
William eventually backed down, wearing the red tunic which has since featured in countless photos, postcards and other memorabilia.
William said in an interview with ABC in 2012: “What I really wanted to wear was the Irish Guards frock coat.
“We had a couple of discussions on this matter but, as I learnt growing up, you don’t mess with your grandmother.
“What she says goes.”
However, he and Kate were still allowed to break a few royal traditions in their grand wedding ceremony, as reported by The Mirror.
William and Kate were allowed to draft their own guest list with the support of the Queen.
The Duchess has marked a number of milestones recently – her 40th comes after she celebrated 10 years of marriage with Prince William in April.
The couple’s romance began when they were at university at St Andrews.
In 2007, William and Kate hit a brief rough patch when they broke up.
Reports from April 2007 also claim that William broke up with Kate via a phone call that she received while at work.
The future Duchess, then 25, excused herself from a meeting and went into a room to be out of earshot of other buyers, Robert Lacey claims in his book Battle of Brothers.
Mr Lacey claimed: “She shut the door for more than an hour. When she came out, she was single.
“They could suss out the truth about where his heart lay, even if he himself could not.”
They got back together in June 2007 and, by 2010, were ready to spend the rest of their lives together.
The Duke of Cambridge returned to work this week after celebrating Kate’s 40th birthday at the weekend.
He hosted an investiture ceremony at Windsor Castle on Wednesday, handing out honours to fashion designer Sir Paul Smith, Sir Clive Lloyd and Derrick Evans, better known as Mr Motivator.
Source: EXPRESS CO UK