Barry Keoghan and Sabrina Carpenter's love story just became Instagram official.

After the "Feather" singer shared a video of herself performing with Taylor Swift onstage at the Grammy winner's Eras tour concert in Sydney, Australia Feb. 23, the Saltburn actor commented on her Instagram post with a queen emoji.

The duet took place two weeks after Sabrina, 24, and Barry, 31, publicly confirmed their romance. The two were photographed packing on the PDA during a night out in Los Angeles.

During her headlining show at Accor Stadium in Sydney, Taylor had brought out Sabrina, her opening act, as a surprise guest to sing a duet of "White Horse," and parts of "Coney Island," while performing on a piano. The latter singer's set was canceled earlier in the evening due to bad weather.

The joint performance was extra special for the Disney star, who was a longtime fan of Taylor before they became friends and colleagues.

In her Instagram post, Sabrina shared a resurfaced tweet she wrote in 2009 when she was 10 years old, which read, "Was trying to enter a Taylor Swift karaoke contest to win tickets and a chance to meet her but they said I had to be 13 :("

The singer captioned her post, "9 year old Sabrina singing white horse would never see this s--t coming! i love you so so so dearly taylor. always have always will."

Several celebrity guests attended the concert: Katy Perry—who years ago sparked feud rumors with Taylor and is rumored to have inspired her song "Bad Blood," Rita Ora and husband Taika Waititi and the "Cruel Summer" singer's boyfriend Travis Kelce, who was accompanied by his former Kansas City Chiefs teammate Ross Travis.

During their visit to Australia, Sabrina and the athletes accompanied the singer on visits to the Sydney Zoo, where Taylor cheered on Ross as he fed a lion.

"Beautifully done," she told him, as seen in a video he shared on Instagram.

Ross also shared a couple of images from the concert, including a video of himself making Taylor's signature hand heart gesture while wearing numerous friendship bracelets as she performed her 2014 hit "Shake It Off" before the some 80,000 fans inside the packed venue. The experience appears to have made the athlete a bona fide Swiftie.

"I understand now," Ross wrote on his Instagram Story. "That. Was. Amazing."

Look back at celebs who have attended Taylor's Eras tour:

"It’s fair to say Sydney always delivers," Rita Ora captioned Instagram photos from Taylor Swift's Feb. 23 show, including a snap with Travis Kelce. "Or shall we say our TayTay @taylorswift always delivers!”

Taylor's dad Scott Swift delivered an epic photobomb.

"Got to see an old friend shine tonight," Katy Perry captioned footage on Instagram from the Feb. 23 concert.

Jessica captioned the moment with friends in Mexico City, "Spamming u w really good @taylorswift Eras Tour content."

The Pretty Little Liars star attended with friends Morgan Pesante, Katie Greenthal and Claire Leahy. "Omg??? @taylorswift putting on a show that was so good I can't even process," she wrote. "Nostalgic, empowering, and sparkly."

The "Bad at Love" singer got in the spirit by making friendship bracelets to trade with fans during the last Los Angeles show.

"Still in the afterglow of the most magical night," the Law & Order: Special Victims Unit star wrote on Instagram Aug. 9 after a bejeweled night out in L.A. "Deepest gratitude to @taylorswift for your poetry and wisdom. You inspire us and connect us to our #delicate tenderness, joy, hope and strength—and most of all, our wish to live and love courageously."

Sharing pics from an L.A. show, Chris Olsen quoted the T.Swift lyrics in his caption, "I DON'T KNOW HOW IT GETS BETTER THAN THIS."

"Eras tour (Dylan's version)," the influencer captioned fits of her rocking a Stella McCartney outfit. "@taylorswift you are a goddess best night ever."

The Hills stars filled a blank space in their calendar with a date night in Los Angeles at the Eras Tour. Heidi Montag captioned their pics, "This was the concert of a lifetime! Legendary! Thank you for the tickets @taylorswift."

"@taylorswift with the fam," Jessica Alba wrote, "what a show!" She and husband Cash Warren celebrated their love story by taking their kids Honor, 15, and Haven, 11, and Hayes, 5.

The Mad Max star danced to "Shake It off" with her kids August and Jackson. "Thank you for the best birthday ever @taylorswift!!!" she wrote. "We had such a great f--king time."

"What a SHOW," Paula Abdul wrote while posting for a photo with Vince Vaughn and Taylor's parents Scott and Andrea Swift in Los Angeles.

The Vanderpump Rules stars made their wildest dreams come true on the floor with Paula.

The "No One singer" attended the Aug. 5 show at SoFi Stadium in Los Angeles with her 8-year-old son Genesis.

The actress attended one of Swift's shows at SoFi Stadium in Los Angeles with Anastasia Beverly Hills cosmetics founder Anastasia Soare and her daughter, Claudia.

The late Kobe Bryant's wife Vanessa Bryant and their daughters Natalia Bryant, 20, Bianka Bryant, 6, and Capri Bryant, 4 attended Swift's show at SoFi Stadium in Los Angeles Aug. 3. While performing her song "22," the singer approached Bianka at the end of the stage, hugged her and gifted her a black hat she typically gives a fan during the number. The family later got to hang out with the pop star backstage.

The Hills alum was ready to be enchanted at the Aug. 4 show.

The New Girl star shared a family photo on TikTok ahead of the Aug. 4 show.

The duo snapped a selfie at SoFi Stadium on the first night of the Eras Tour in Los Angeles, with Elizabeth Banks writing of Taylor's performance, "She was an Angel and a Unicorn and Pure Magic."

Elizabeth took a pic of Sarah Paulson showing off her Eras Tour merch from the Casamigos suite.

"The first night of the LA Eras tour was everything!" Mindy Kaling wrote after the Aug. 3 show. "@haimtheband set the tone by destroying in their home town and then @taylorswift, well, did her bejeweled thing and 70,000 of us were like 'how can we know every single lyric to 5 hours of songs?'. There were no highlights. It was all highlight."

The couple headed to Night One of the tour in Los Angeles, with Becca captioning their look with the "Fearless" lyrics, "I know I wanna ask you to dance right there, in the middle of the parking lot."

Brie Larson shared a pic from her view of the show in Los Angeles.

Brie captured a video with fellow Marvel star Lupita Nyong'o.

The Hills alum was ready for it on Aug. 4 in L.A.

Kobe and Vanessa's 20-year-old daughter shared a hug with Taylor after the show.

Kobe Bryant's wife Vanessa Bryant paid tribute to the late basketball player with her outfit for the Aug. 3 concert.

Rocking a custom "Taylor" shirt, the High School Musical star was ready for the Aug. 3 show in Los Angeles.

Gigi Hadid partied with her makeup artist Patrick Ta at the show in Santa Clara, Calif. He captioned their pic, "I Want To Bottle This Moment Up Forever."

For the latest breaking news updates, click here to download the E! News App