The royal gave a nod to Irish tradition by wearing a green ensemble.
She wore a bold green tweed blazer which had white stitching throughout.
The emerald item is reportedly from Zara and was on sale for £59.99.
The Duchess of Cambridge’s blazer was buttoned at the waist which created a v-neckline.
Wearing a green outfit to celebrate the national holiday is something Kate has often done over the years.
Her look gave another nod to Ireland as she wore a gold shamrock necklace and earring set.
The Duchess has worn the jewellery items before and the earrings appeared to be the Daniella Draper Gold Mini Cupid Hoops With Baby Shamrock Charms.
The sterling silver earrings have a gold hoop with shamrock charms hanging from each piece.
The royal wore her long dark brown locks in a side parting and styled into a straight blow-dry.
She stuck with her signature make-up by opting for a subtle look.
The royal highlighted her natural looks with a nude lipstick and slick of blusher.
Stood next to Prince William, the video message appeared to be filmed inside their home.
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The royal line of succession – who outranks who?
The line of succession to the British throne dictates the order in which each member of the Royal Family would ascend to the throne.
It is also seen as a ranking of importance with the head of the line, the Queen, taking the place of ruler.
Older children come before younger children. Traditionally boys came before girls, but this law was changed on 26 March 2015 before the birth of Prince William’s first child.
Incredibly, Catholics are still excluded from the line of succession, as are children born outside of wedlock.
The royals, who usually stick to a strict protocol when appearing in public, often arrive at events in ascending order of importance, with the most important royal arriving last.
Prince Charles, 72, is currently first-in-line to the British throne, followed by Prince William, 38, his oldest son.
Then comes Prince William’s children, George, seven, Charlotte, five, and Louis, two, and they are followed by Prince Harry, 36. Prince Harry is succeeded by his son Archie Harrison, born in May 2019.