To mark the special occasion, the Smile hitmaker shared a sweet post on Instagram that gave fans a new look inside their intimate Las Vegas ceremony, including several photos of her daughters who acted as flower girls.
The couple enjoyed a romantic dinner to mark one year of marriage, with a video of David smashing their tasty dessert that read 'Happy Anniversary.'
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Meanwhile, further snaps showed Ethel and Marnie, who she shares with ex-husband Sam Cooper, dressed in cute matching pink ruffled dresses and holding pink and orange roses.
They were standing inside the famous Graceland Wedding Chapel in Las Vegas with Elvis impersonator Brendan Paul in the background, who carried out the ceremony. White flowers decorated the aisle and a camera was set up to capture the nuptials.
Lily's daughters Ethel and Marnie were flower girls
Lily broke with tradition by wearing a short Dior blazer dress, which she paired with black suede platforms heels and a veil, while another snap showed her donning a leopard print Ganni coat.
Her elegant outfit was visible as she tucked into a cheeseburger! Lily and Hellboy star David ditched the traditional sit-down meal in favour of their favourite takeaway, In-N-Out burgers, in the car park of the chapel.
The couple chose In-N-Out burgers
"1 year down with this guy. Happy Anniversary baby @dkharbour. I prefer my life with you in it. You can stay," she captioned the post.
Fans were delighted to catch another glimpse of their big day, which was only attended by Ethel and Marnie. "You’re awesome together," commented one follower, and another remarked: "Happy 1 year to you both…xx relationship goals!!!" A third added: "Best wedding ever."
The couple got married inside the famous Graceland Wedding Chapel in Las Vegas
Lily and David went public with their relationship in 2019 after they were spotted together at a West End production of The Lehman Trilogy.
They were spotted kissing at Madison Square Garden in October and went on to make their red-carpet debut at the SAG Awards in January 2020.