No doubt his "beloved mother" will be on his mind on Sunday, after paying tribute to the late monarch during his Commonwealth Day service speech on Monday. Take a look back at some of Charles and the late Queen's touching moments together...
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In his speech at Westminster Abbey, Charles described how Commonwealth Day was a moment of pride for the late Queen Elizabeth II who "dedicated her long and remarkable life" in service to the "Commonwealth family".
Last year, the then-Prince of Wales and Duchess of Cornwall shared a touching Mothers Day tribute on their Clarence House social media accounts.
"On Mothering Sunday, we celebrate all the Mothers in our lives and are thinking of those who cannot be with their Mothers today," the Twitter post read.
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Charles's tribute to the Queen on Mother's Day 2022
The images showed Charles with the Queen as they planted a tree together in the grounds of Windsor Castle.
The future King donned a camel coat while the Queen wrapped up in a bottle green overcoat and wore one of her signature printed scarves.
Charles became heir apparent at the age of four
The second photo showed Camilla with her late mother, Rosalind Shand, who died at the age of 72 in 1994.
Charles's coronation will take place at Westminster Abbey on 6 May and celebrations will continue over the Bank Holiday weekend with the Big Lunch, a concert at Windsor Castle and the Big Help Out.
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