The Princess of Wales continued the theme of red, white and blue for the coronation weekend with a sky-coloured blouse on bank holiday Monday.
Kate looked the epitome of country chic in a loose-fitting, long-sleeved blue top and casual dark khaki skinny jeans during a volunteering day for the Big Help Out.
Alongside the Prince of Wales and their three children, the 41-year-old helped to renovate and improve the 3rd Upton Scouts Hut in Slough.
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The princess made sure she was dressed practically for the occasion with flat Chelsea boots.
She wore her long brown hair in a relaxed style and ensured Louis’s outfit co-ordinated perfectly, with the five-year-old in a pale blue polo shirt and shorts.
 Princess of Wales, Prince Louis and Princess Charlotte take part in the Big Help Out. AP
Kate wasn’t afraid to get her hands dirty either and could be seen digging a patch of dirt and picking up a wheelbarrow full of sand before trying her hand at archery.
The royals also helped reset a path, revarnished a door, and contributed to a mural on the front of a building.
Prince Louis even got to operate a digger with his dad.
Kate’s outfit choice ends a spectacular weekend of fashion choices for the royal.
She recycled a sleek red suit to Sunday’s Coronation Concert – an Alexander McQueen outfit she previously wore for a Shaping Us event last January.
 Kate, Princess of Wales, Prince George and Prince Louis toast marshmallow. AP
It had an unusual asymmetric, wrap blazer, which she wore with a silver necklace by Van Cleef & Arpels.
Earlier on Sunday, Kate had chosen a £298 pale blue linen blazer by Reiss and black trousers to meet royal fans at a Big Lunch gathering in Windsor.
For the coronation ceremony itself, Kate wore a deep blue Royal Victorian Order mantle edged in scarlet, over an Alexander McQueen embroidered ivory silk crepe dress.
Breaking from tradition, she chose not to wear a tiara, instead topping her outfit with a silver headpiece by Jess Collett x Alexander McQueen.
In a touching tribute to William’s late mother, Kate wore pearl and diamond earrings that had belonged to Diana, Princess of Wales.