American actress. She is best known for her role as Dr. Addison Montgomery on the ABC television dramas Grey's Anatomy and Private Practice Kate Walsh accidentally revealed her own relationship milestone during an Instagram Live on Wednesday.

The Grey's Anatomy star accidentally let it slip that she and boyfriend Andrew Nixon were engaged during an Instagram Live she did with actress Amy Brenneman to commemorate the 15th anniversary of their former show, Private Practice.

"Here comes the jungle cat, that is my fiancé," Kate, 54, said during the Oct. 5 video as she panned the camera to Andrew, who smiled and waved.

Catching the leak, Amy noted, "She just 100 percent outed your engagement."

Kate replied, "I did, I just outed our engagement," as Andrew said, "Aww."

During the Live, the 13 Reasons Why actress flashed her massive diamond ring on camera and shared a kiss with her fiancé. Kate later posted a photo to her Instagram Stories of two martini glasses along with the caption, "Celebrating with w/@andynix1!!"

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Walsh, whose ring could be seen during the video, then confirmed, “I did. I just outed our engagement.”

News broke in February 2021 that the “Umbrella Academy” star was in a relationship with Nixon, whom she reportedly met on a cruise.

Walsh reportedly met her husband-to-be on a cruise in early 2020. The pair now share a home in Perth, where they spent lockdown together during the height of the pandemic, according to Digital Spy.

Nixon is part of a family farming enterprise called Nixon Farming in the Moora/New Norcia region of Western Australia, where they run Merino sheep as well as rotate wheat, barley and canola.

Walsh is set to reprise her role as Dr. Addison Montgomery in season 19 of Grey's Anatomy, which premieres on ABC in the US today (October 6). UK viewers will be able to watch the latest season on Disney+ from October 26.

The couple have been living together in Perth, Australia, with Walsh telling the Daily Telegraph in August 2020 that she got “stuck” away from home during the COVID-19 pandemic.

“I didn’t really want to go back to New York in the middle of a pandemic when it was pretty gnarly to say the least,” the “13 Reasons Why” alum said at the time.

“I couldn’t go home initially, and now that I can, I don’t really fancy going back,” she continued. “I have my own mother saying, ‘Don’t come home,’ my 86-year-old mum. … We are in a very challenging time!”

This will be Kate's second time down the aisle. In Sept. 2007, she married producer Alex Young in front of approximately 100 guests, including Grey's Anatomy co-stars Katherine Heigl, Chandra Wilson, Sara Ramirez and Justin Chambers.

After 15 months of marriage, Alex filed for divorce from Kate citing irreconcilable differences as the reason for the split, according to NBC Washington. In a joint statement shared with Access Hollywood in 2008, the former couple said that they will "remain on friendly terms and sincerely hope the media will respect their privacy during this difficult time,” according to E! News.

Kate and Alex's divorce was finalized in 2010.

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Sources: E! News, Page Six, Digital Spy