Fans think Taylor Swift and Katy Perry are cooking up a collaboration, thanks to some subtle hints on social media

• Fans of Taylor Swift and Katy Perry think the two stars could be working on a collaboration, or some kind of joint announcement.
• The theory comes from subtle similarities in their recent social media posts.
• Perry announced on Thursday that her next single will be called "Daisies." The same day, Swift posted a photo of herself wearing a sweater with daisies.
• The Twitter account for "American Idol," on which Perry is a judge, wrote of her new song: "We can't wait to play this like 1,989 times in a row." Fans think this is a reference to Swift's album "1989," named after her birth year.
• Swift and Perry have had a rocky history, but famously cemented their mended friendship in Swift's 2019 music video for "You Need to Calm Down."
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Fans of Taylor Swift and Katy Perry think the two stars could be cooking up a collaboration, or getting ready to announce some kind of joint project.

The theory, which has been spread widely by fan accounts on Twitter, is rooted in subtle similarities in their recent social media posts.

The biggest potential clues relate to Perry's forthcoming song. The "Never Really Over" singer revealed on Thursday that her next single, coming on May 15, will be called "Daisies."

Less than two hours later, Swift posted a photo of herself at home, wearing a sweater with daisies on it.

Swiftian sleuths found out the sweater is part of the "Bali Daisy Jane Set" from Free People.

The caption for Swift's photo references her 2017 album "Reputation." The snake emojis are tied to the visual themes of that era, and "biiig isolation" is a play on the "End Game" lyric, "Big reputation / Big reputation / Ooh, you and me, we got big reputations."

Interestingly, on the album's fourth track "Don't Blame Me," Swift references daisies when singing about personal growth and the healing power of supportive relationships: "I once was poison ivy, but now I'm your daisy."

A few hours after Swift's post, the Twitter account for "American Idol" — for which Perry is a judge — reacted to the news of Perry's new music: "We can't wait to play this like 1,989 times in a row."

Fans think 1,989 is far too specific to be a coincidental choice. It looks like a reference to Swift's Grammy-winning album "1989," which was named after her birth year.

All this comes after Perry posted a photo of daisy shoes that she designed for her Katy Perry Collections.

"Sticks and stones may break your bones, but Daisies are the friendliest flower," she wrote alongside the photo on Instagram.

Although "sticks and stones" is a popular phrase, it could also be a reference to Swift's song "You Need to Calm Down," which features the lyric, "Snakes and stones never broke my bones."

After an infamously rocky history, Perry had a major cameo in the music video for that very song, which artfully cemented the singers' mended friendship.

It's certainly possible that "Daisies" is actually a duet between Perry and Swift, but it looks like fans will have to wait and see if that theory pans out.

• Read more:
• Taylor Swift blames the media for her feud with Katy Perry and says they talked for hours after reconciling
• The full history behind all of Taylor Swift's biggest celebrity feuds
• Everything you missed in Taylor Swift's 'You Need To Calm Down' music video
• Colbie Caillat says working with Taylor Swift was a 'fascinating' experience: 'She makes you feel like she's known you forever'