"Secrets out!! So happy for you guys! Been a long time comin'," Brandi Cyrus wrote on a screenshot of the couple's sweet wedding photo

Miley Cyrus and Liam Hemsworth’s love can’t be tamed.

The singer’s older sister Brandi — who was in attendance at the newlyweds’ surprise wedding on Sunday — congratulated the stars on their new union on her social media account.

The “Your Favorite Thing” podcast host, 31, posted to Instagram on Wednesday to share her excitement for the pair, who gave family and friends an early Christmas present when they secretly tied the knot.

“Secrets out!! So happy for you guys! Been a long time comin’,” Brandi wrote on a screenshot of the couple’s sweet wedding photo.

Brandi Cyrus shares sweet wedding message to sister Miley and Liam Hemsworth on Instagram on Wednesday
| Credit: Brandi Cyrus/Instagram

“Love you both,” she added at the bottom of the post.

Just hours before, the singer, 26, confirmed the happy news when she posted some adorable photos from the intimate ceremony to her social media accounts.

Miley Cyrus and Liam Hemsworth

In one snap, she and her groom, 28, are all dressed up in their wedding best — a floor-length white gown for her and black tux for him — as they share a smooch. And in two other photos, the actor has his arms wrapped around Miley’s waist as they share a quiet moment together in front of what appears to be an altar adorned with roses and baby’s breath.

Miley captioned the photos of her embracing Hemsworth: “12.23.18” and “10 years later …..” On the photo of them kissing, the singer wrote: “This is probably our one – millionth kiss.”

Miley Cyrus and Liam Hemsworth
| Credit: Miley Ray Cyrus/Twitter

Even in the comments of her posts, the singer couldn’t contain her excitement about the big day. When a fan told Cyrus on Instagram, “Congratulations you married the hottest man in Hollywood!!!!,” Cyrus enthusiastically agreed. “I knooooowwwww right” she wrote, as seen by popular fan site Comments by Celebs.

Photos and video posted to the Instagram story of the couple’s surfer friend Conrad Jack Carr on Sunday showed Hemsworth and his brothers Chris and Luke doing a “shotski,” with Mr. and Mrs. balloons in the background. Another photo showed the newlyweds in front of cake and cupcakes, with the singer’s mother Tish in the frame.

Miley Cyrus and Liam Hemsworth
| Credit: Conrad Carr Instagram

Miley and the Hunger Games actor’s private wedding comes after a rocky, on-again, off-again relationship between the Last Song costars. She and the Australian actor dated for years before he proposed in 2012, but the two ended their engagement and broke up a year later.

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They reconnected in 2015, however, and the couple’s romance was back in full swing by summer 2016, including dinner with Hemsworth’s parents, date nights and spending holidays together.

Until recently the love birds lived with their seven dogs, two pigs and two miniature horses in a shared Malibu home, which burned down in one of the three devastating California wildfires.

On her last album, Miley sang about finding love again with Hemsworth. Sings the star on her hit song “Malibu”: “I’d spend the rest of my life just standing here talking / You would explain the current, as I just smile / Hoping I just stay the same and nothing will change / And it’ll be us, just for a while.”