Katy Perry crashed a wedding in St. Louis over the weekend

An extra guest at the wedding is the stuff of bridal nightmares. But for Hayley Rosenblum and Blonie Dudney, who got married in St. Louis over the weekend, a wedding crasher turned out to be a teenage dream.

Photos posted to a Katy Perry fansite show Perry in a jumpsuit and a baseball cap, posing with the smiling bride and groom. Video shows the couple posing for a photo with the pop star, with plenty of cheers and laughs in the background.

Wedding guest Sarah Kline, who works for the groom, said that the wedding was “out of a bridal magazine” even before Katy Perry walked in. We wondered if Perry had a connection to the bride and groom, but Kline tells Yahoo Lifestyle that Perry full-blown crashed the wedding.

“It was said loud and clear: ‘Katy Perry is crashing the reception,’’” said Kline. “We went out and danced for a little bit and videoed her dancing with the bride and groom.” She even stopped to take pictures with whoever asked. Kline snapped a photo for her eldest daughter, and when she was struggling to frame the photo, Perry herself grabbed her phone and snapped the selfie.

“It was an unforgettable night for everyone! If this is [any indication] of how their marriage will be, they’re in for a lifetime of fun and surprises,” says Kline.

Perry is the latest of many celebs who have used the fame card to crash a wedding. From Bradley Cooper to Beyoncé and Jay-Z to Robert Pattinson to Tom Hanks, there’s apparently nothing wedding-crashing celebs love more than a photo op and a free piece of cake.

While we won’t encourage any uninvited guests, a celebrity appearance definitely ensures your guests will never forget your wedding. As Kline tells us, “I didn’t think the night could have been anymore perfect … until the end of the night.”

Read more from Yahoo Lifestyle:

• This little girl was supposed to be a flower girl, but ‘napping is life’

• This couple’s wedding photos are the most beautiful thing on the internet

• Lupita Nyong’o’s hairstylist is selling an $18 bottle of water for your hair — and it’s not a gimmick

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