The royal couple made a special trip to Windsor Guildhall to meet volunteers and operational staff to thank them for their involvement in the late monarch's committal service held in the grounds of Windsor Castle. As per royal mourning guidelines, the royal couple appeared in black as a show of respect for the late Queen.
WATCH: Prince William reveals how he is coping with his grief
Speaking to the group, William shared a touching moment that happened following the passing of his grandmother, while the family were still in Scotland.
He explained that he had seen five rainbows over Balmoral after the Queen had passed away. Kate then added: "Her Majesty was looking down on us."
The Queen had been staying at her Scottish residence of Balmoral on 8 September when her health deteriorated.
Rainbows were seen over Buckingham Palace shortly after the Queen's death
On the day that the Queen passed away, rainbows were seen over Buckingham Palace and Windsor Castle. Another rainbow formed over Westminster Hall on the day before her lying in state came to a close.
Her Majesty's state funeral was held on Monday 19 September, taking place at Westminster Abbey before the committal ceremony that took place in Windsor.
Prince William had a strong bond with his grandmother
The late monarch was then interred in the King George VI memorial chapel alongside her beloved husband Prince Philip, her father, King George VI, the Queen Mother and sister Princess Margaret.
Following her burial, the ledger stone was updated to reflect that the Queen and Prince Philip now laid in rest there; the Duke of Edinburgh was previously interred in the Royal Vault.
The full stone now reads: "George VI 1895-1952," followed by "Elizabeth 1900-2002." There is then a metal garter star before the final two names: "Elizabeth II 1926-2022" and "Philip 1921-2021."
Although Margaret is buried alongside her family, her name doesn't feature on the ledger stone as her ashes are interred inside the wall.
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