The actress has been married for 18 years

Mariska Hargitay and her husband Peter Hermann celebrated their 18th wedding anniversary over the weekend, and to mark the occasion, the Law & Order: SVU actress decided to share a stunning black-and-white photo from their big day.

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The never-before-seen snap showed the Olivia Benson actress dressed in a strapless satin gown with a deep sweetheart neckline with her brunette tresses swept up into an elegant updo while her husband, who is best known for his role on , is dressed in a sharp black suit with accessorised with a rose boutonnière.

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In a second slide, Mariska shared a more recent black-and-white snap of the two of them cuddled up together and looking blissfully happy while enjoying a boat ride. "Eighteen years. Grateful. In love. Together," she captioned the post as she shared it on Instagram.

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It immediately sparked a huge reaction from her followers, who rushed to the comment section to congratulate the couple on reaching the marriage milestone. One wrote: "Happy anniversary! Wishing you both many many many more years of love happiness and adventure."

Mariska delighted her followers with the stunning black-and-white snap

Another said: "If there is such thing as love you both are the proof. Congratulations. And much laughter and joy. For ever," and a third added: "I want this in life omg y'all are goals!"

The couple tied the knot at an intimate ceremony in Santa Barbara, California, in 2004 after just over two years of dating and have the sweetest love story.

Mariska and Peter tied the knot in 2004

They met on the set of Mariska's NBC drama all the way back in 2001 when they were both in their mid-thirties when Peter was booked for a recurring role in the police procedural drama's third season.

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Away from the cameras, the two actors are proud parents to three children. They welcomed their first child together, a son named August, in 2006. Five years later, in 2011, they decided to grow their family again, this time choosing to adopt a baby girl named Amaya Josephine. Less than a year later, they adopted another child, a baby boy named Andrew.

Opening up about becoming an adoptive mother, just like her character on Mariska told  "August wanted siblings, and Peter and I both envisioned this big family because we both come from that. Plus, we just had so much love to give," adding that it was "always part of the plan" to adopt.

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