Kate Middleton and Prince William Say Goodbye to Queen: 'A Mother, a Grandmother and a Great Grandmother'

The Prince and Princess of Wales are bidding Queen Elizabeth a final farewell.

Following the monarch's funeral and committal service on Monday, her grandson Prince William and granddaughter-in-law Kate Middleton shared a statement in the late monarch's memory on their official Twitter page. "Goodbye to a Queen, a mother, a grandmother and a great grandmother," they wrote alongside a photo of pallbearers carrying her coffin.

The couple returned to the venue of their 2011 wedding for Queen Elizabeth's state funeral on Monday at Westminster Abbey. Kate, 40, arrived for the funeral with their son Prince George, 9, and daughter Princess Charlotte, 7, but their 4-year-old son Prince Louis was not in attendance.

William, 40, arrived with his father, the new King Charles III. He also walked side-by-side with his brother, Prince Harry, during the procession.

RELATED: King Charles, William and Harry 'Deeply Affected' at Queen Elizabeth's Funeral: 'It Was Human'

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Lesley Garven MBE, manager of the Blind Veterans UK, tells PEOPLE that the monarch and his sons appeared emotional during the services.

"They were flushed. You could see that William and Harry and King Charles were deeply affected," he says. "Really deeply emotionally affected by the whole thing, and that really touched me.

Getty Prince William and Kate Middleton take their seats with son Prince George and daughter Princess Charlotte at Queen Elizabeth II's state funeral

"They were obviously holding it together, but when you are so close to somebody you can really feel it and see it, and I think that was probably quite ... it was human. It was real human feelings. Being in there was quite up close and personal and intimate. And it was that whole feeling of, 'This is somebody's mother and grandmother.' Below the pageantry, you could really feel it. The real, raw feelings of people," Garven adds.

After the Queen died at age 96 on September 8, Prince William shared a heartfelt statement in his grandmother's memory.

Tristan Fewings/Getty Prince William and brother Prince Harry walk side-by-side in procession to Queen Elizabeth II's state funeral at Westminster Abbey

"On Thursday, the world lost an extraordinary leader, whose commitment to the country, the Realms and the Commonwealth was absolute," he wrote. "So much will be said in the days ahead about the meaning of her historic reign.

"I, however, have lost a grandmother. And while I will grieve her loss, I also feel incredibly grateful. I have had the benefit of The Queen's wisdom and reassurance into my fifth decade. My wife has had twenty years of her guidance and support. My three children have got to spend holidays with her and create memories that will last their whole lives," he continued.

"She was by my side at my happiest moments. And she was by my side during the saddest days of my life. I knew this day would come, but it will be some time before the reality of life without Grannie will truly feel real," Prince William added.

RELATED VIDEO: Prince George, 9, and Princess Charlotte, 7, Join Royal Family Procession at Queen Elizabeth's Funeral

The Queen's coffin traveled to Westminster Hall in a solemn procession on Wednesday, and it has since been lying-in-state for mourners to pay their respects. More than 2,000 people from around the world gathered Monday at Westminster Abbey in London for the Queen's state funeral before she was laid to rest at Windsor Castle.

In a his first speech to the nation as monarch, King Charles confirmed that Prince William and Kate will be known by the titles of Prince and Princess of Wales. Their new titles extend to their three children as well.