Fans at Anderson East's Valentine's Day 2016 show in Northampton, Mass., got quite the surprise: a guest appearance by Miranda Lambert! The country superstar joined her boyfriend onstage to cover a Mariah Carey classic.

East played Northampton's Pearl Street Nightclub on Sunday night (Feb. 14), and during his version of Carey's "Always Be My Baby," Lambert hopped up on stage to provide harmonies. East puts a bluesy spin on the '90s pop hit, which he has been covering at a few recent shows. Press play on the video below to watch the couple (and Gwen Sebastian!)'s performance.

East, 27, is an Americana / R&B / pop artist from Athens, Ala. Born Michael Cameron Anderson, he now lives in Nashville and released his major-label debut, Delilah, in July. He and Lambert have been dating since December of 2015; they confirmed the rumors of their relationship with an Instagram photo on New Year's Day. Both artists are featured on the upcoming Southern Family concept album.

Lambert and now-ex-husband Blake Shelton announced their divorce in July, after four years of marriage. Both artists have been relatively quiet about the circumstances surrounding their split, but in an interview with Cosmopolitan, Lambert said simply, “Marriage is a tough business, and we gave it our best college try.”

East's next show is scheduled for Tuesday (Feb. 16) in Pittsburgh, Pa. A complete list of all of his upcoming tour dates is available on his official website.

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