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8 Hottest Irish Stars in Hollywood -- Hear Their Swoonworthy Accents!
Downey and David Arquette fully embraced their inner Irishman on the holiday, showing off their head-to-toe green ensembles, while other stars like Witherspoon celebrated with something a little more subtle.
"Green drink, green dress. It’s only right. Cheers to #StPatricksDay! ?," the Big Little Lies star captioned a shot of her looking perfectly festive in a patterned dress while holding a glass of something green.
See Downey and Arquette's looks below, as well as how others celebrated the holiday.
Today would be a good day to deploy these #StPatricksDay images, because today..... THE WHOLE GALAXY IS IRISH. 💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚💚😜 pic.twitter.com/09xeCbJept
Kate Middleton and Prince William, meanwhile, spent the day at the St. Patrick's Day parade in Hounslow, west London, where they visited the 1st Battalion Irish Guards, and had a pint of Guinness (well, water for Middleton).