The best wedding singer for the Singers! Shortly after news broke of her split from Calvin Harris, Taylor Swift surprised a couple at their wedding in New Jersey on Saturday, June 4, and the groom’s sister, Ali Singer, has shared a video of the touching moment and the full performance at the reception.

Back in April, Ali wrote a letter to the pop superstar explaining that her brother, Max Singer, had married his wife, Kenya Smith, in his sick mother’s hospital room so she could be part of the special day and they even picked a Taylor Swift song for their mother-son dance. Sadly, she passed away before she could watch Max tie the knot in the big ceremony.

“For those of you who missed the moment, Max chose ‘Blank Space’ as his mother-son dance,” Ali said in her speech of their hospital room dance. “An oh-so-fitting song for probably the biggest Taylor Swift fan.”

“Max, Kenya, we all wish mom was here, and I can confidently say she’s smiling down on us right now, and telling us to get the party started. … We’re going to get this life together started the way you started it the first time around with your marriage in that little room. In the words of Sheryl Sandberg: 'We want option A, but option A’s not available, so let’s just kick the s--t out of option B,'” Ali said before bringing out Swift to a chorus of screams from the guests.

The newly single songstress, 26, performed a beautiful rendition of “Blank Space” on the piano as Max and Kenya danced in front of her. Soon, all the guests joined them on the dance floor. “Alright, I want to talk about the fact that when I wrote this, I never in my life imagined I would be playing it at a wedding,” Swift joked on the microphone. “But what Max and Kenya want, they get!”

The singer, who was clad in a gorgeous strapless dress and, of course, wore her signature red lip, has previously said that “Blank Space” is a song that made fun of the rumors surrounding her dating life. “Oh, a serial dater. She only writes songs to get emotional revenge on guys. She’s a man hater. Don’t let her near your boyfriend. It was just kind of excessive and, you know, at first it was hurtful and then I found a little comedy in it,” she told NME of the track in 2015. “Half the people got the joke. Half the people really think that I was really owning the act that I’m a psychopath, which is fine.” (On Wednesday, June 1, Us Weekly confirmed that Swift split from Harris after 15 months of dating. “The only truth here is that a relationship came to an end & what remains is a huge amount of love and respect,” the DJ later wrote on Twitter.)

Swift, who also apologized to the newlyweds for “wedding crashing,” even brought a gift: a personalized painting that said, "So it’s gonna be forever" with the date. She posed for photos with the wedding party and several guests, even posting a few snaps on her Instagram account. “Third wheel,” Swift wrote next to a photo of Max and Kenya.

Swift’s not the only public figure to congratulate the couple. Facebook COO Sandberg even saw the video and commented, “What a beautiful tribute to your mom. Congratulations on the wedding — and kick the s--t out of Option B!"

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