William stopped for a pint of Guinness during the celebration, while Middleton stuck to water.
No one rocks a festive ensemble like Kate Middleton!
The 35-year-old royal and her husband, Prince William, made their annual appearance at the St. Patrick's Day parade in Hounslow, west London, on Saturday, where they visited the 1st Battalion Irish Guards, of which William is a colonel.
Middleton looked chic as ever in a green Catherine Walker coat, a matching Gina Foster Meribel hat, black gloves and black suede pumps. The brunette beauty, who is expecting her third child with William next month, handed sprigs of shamrocks to officers and warrant officers, and met with their mascot, Irish Wolfhound Domhnall.
The couple later stopped for a celebratory glass of Guinness, but Middleton opted for water.
A source recently told ET that Middleton has been sharing fashion tips with her future sister-in-law, Meghan Markle, ahead of her upcoming wedding to Prince Harry on May 19.
"Both Kate [Middleton] and Camilla [Duchess of Cornwall] have been doing what they can to make sure Meghan knows she’s loved and supported as she navigates her life as a future royal," the source said, explaining that becoming a royal member can be isolating. "She’s been embraced by the royal family. She’s also been exploring various charitable avenues she'd like to pursue after she gets married."
See more on Markle and Middleton in the video below.
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