HAIM Promises 'Debauchery' When They Hit the Road With Taylor Swift

Sam Smith may have walked away with the GRAMMY for Best New Artist on Sunday night, but HAIM is taking a cue from their pal Taylor Swift.

The "Shake It Off" singer playfully referenced her own 2008 loss in the category during the awards ceremony, assuring the rest of the Best New Artist nominees that they would all be "fine" in the end. For HAIM, that future includes an opening slot on Swift's 1989 tour.

WATCH: Beyonce, Taylor Swift and HAIM Dance During Jay-Z and Justin Timberlake's Show

ETonline caught up with the girls on the Roc Nation pre-GRAMMY brunch red carpet, where they promised "a party" and "debauchery" when they hit the road with Swift. See more from their interview in the video above.

The sisters have spent plenty of time partying with Swift lately, including a recent trip to Hawaii and a dance party in the audience at Sunday's GRAMMYs. Thanks to a prime seat right behind the awards-show-dancing-queen herself, we saw plenty of HAIM in the audience cutaway shots.

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"We love to dance," they told ETonline on Saturday. "We've been dancing since we were babies."

But at the GRAMMYs, they said, "we're gonna be like drunk moms at a bar mitzvah!"

Mission: accomplished!

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And even though they didn’t have a shiny new trophy to bring home at the end of the night, the girls are taking the entire experience in stride.

"We are such fans of everyone in our category that honestly, whoever wins, we're happy," the said. "We're just so happy we get to sit on the floor. That's a big deal for us."

HAIM will join the 1989 tour on select North American dates this summer, beginning July 10.

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