Fans were thrilled to find out the lineup of guests who would be performing on Taylor Swift's upcoming "The Eras" tour, but nothing could be more exciting than HAIM themselves; how did their friendship blossom through the years?

Speaking to E! News about their upcoming gig as the pop star's opening act at some of her tour dates, sisters Alana Haim, Danielle Haim, and Este Haim expressed their excitement as they have been friends with Swift for years.

Alana said they're currently getting over the fact that they are going on tour again and are "just excited," and the best part about it is they would do it with a friend which is "going to be so much fun."

The sister has been secretive over what songs they would perform on the tour, but fans are speculating that they would have an on-stage collaboration with the tracks "No Body, No Crime" and "Gasoline."

Este teased fans with her answer, saying "I don't know, will there be?"

This isn't the first time Swift and HAIM would be collaborating together on a tour as they previously performed on Swift's "1989 World Tour" in 2015.

Other performers who will grace Swift's stage for the upcoming "Midnights" tour include Paramore, Phoebe Bridgers, MUNA, OWENN, Gracie Abrams, beabadoobee, and GAYLE.

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Taylor Swift, HAIM Friendship

According to UMusic, their connection began in a 2013 interview when the sisters were asked a question about who would the pop star date next.

Even though they aren't friends yet at the time, the trio seemingly defended the singer, inviting her to come out with them and party because they don't need guys to be happy.

The following year, Swift officially followed the siblings on Instagram before interacting with them online a few months later.

In a previous interview, HAIM revealed in an interview their first-ever interaction in real life, saying they were hanging out with Swift one night and their dinner last for over seven hours.

"It was a long dinner, it was just laughs and I was like 'oh my gosh you are literally one of us,'" they said. Since then, they started hanging out with the pop star whenever they get a chance, especially during the 4th of July.

Earlier this year, Taylor Swift surprised fans by appearing at one of HAIM's shows and they mashed up "Gasoline" and "Love Story" together.

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