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

Prince George and Princess Charlotte joined their parents in honoring their great-grandmother Queen Elizabeth at the late monarch's state funeral on Monday.

George, 9, and Charlotte, 7, took part in the royal family procession behind the Queen's coffin alongside Prince William and Kate Middleton as the family made their way down the aisle of Westminster Abbey. Kate, 40, escorted the little ones into the service, though William, 40, arrived earlier alongside King Charles III.

Prince George, Kate Middleton, Princess Charlotte and Meghan Markle

William and Kate spent last week carefully considering whether to include their eldest two children in the procession and service, PEOPLE understands. With the eyes of the world on them, their parents kept in mind the fact that George and Charlotte were at Westminster Abbey for Prince Philip's memorial service in March.

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George and Charlotte are several years younger than William was when he attended his mother Princess Diana's funeral in 1997 at the age of 15. Prince Louis, 4, was likely deemed too young to join the rest of the family for Monday's funeral.

BBC Royal family processional

William revealed that the ceremonial procession of Queen Elizabeth's coffin from Buckingham Palace to Westminster Hall last week reminded him of the same ritual following the death of his mother.

"He said how difficult it was yesterday and how it reminded him of his mum's funeral," said mourner Jane Wells, The Telegraph reported. "Catherine said it's just been such a difficult time for all of them, for the whole family."

Last week, Charles, 73, addressed the United Kingdom for the first time after the Queen died at the age of 96. Among the changes announced, Charles shared that Prince William and Kate, both 40, had inherited the titles of Prince and Princess of Wales.

PHIL NOBLE/POOL/AFP via Getty Prince George, Princess Charlotte and Kate Middleton

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Their three children — who are now the second, third, and fourth in line to the throne — go from being Princes and Princess of Cambridge to being Princes and Princess of Wales. Therefore, they are now Prince George of Wales, Princess Charlotte of Wales and Prince Louis of Wales.

At a 40-minute walkabout outside Windsor Castle on September 10, the new Prince of Wales opened up to one well-wisher in the crowd about his family. Elaine Gee, 58, a teacher from Wokingham, spoke to William about the difficulty in explaining the Queen's death to her primary school pupils.

BBC Prince William, Prince George and Kate Middleton

"I told him how I work at a school and how it's been a strange year celebrating the Jubilee and now it's all changed and we are talking about this," Gee told PEOPLE. "He spoke about George, Charlotte and Louis, saying that they were trying to keep some sense of continuity for them at school and keep things as normal as possible."

Samir Hussein/WireImage Kate Middleton, Princess Charlotte and Prince George

Prince George, Princess Charlotte and Prince Louis were photographed going to a preview day of classes at their new school, Lambrook, just one day before the Queen's death.

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Kate told another well-wisher outside Windsor Castle that Prince Louis had a sweet reaction to the news of Queen Elizabeth's death, saying, "At least Grannie is with Great-Grandpa now," according to The Sunday Times' royals editor Roya Nikkhah.