It isn't such a great day for Taylor Swift as her former beau Calvin Harris posted a series of tweets attacking her. The songstress hasn't addressed Harris' rant yet for she appears to be making the most out of her vacation with beau Tom Hiddleston. Swift devoted her day to visiting sick kids at Brisbane's Queensland & Lady Cilento Children's Hospital.

https://www.facebook.com/childrenshealthqld/videos/1033751173399249/

In a video clip, the Styles singer sits beside a boy on a hospital bed. She plays the guitar and sings her single Shake It Off. A group of other patients also chimes in to her mini performance. The hospital took to Facebook to express its gratitude to Swift's time.

"Thank you Taylor Swift for dropping by the Lady Cilento Children's Hospital this afternoon to give our patients and families a special surprise they'll never forget. They'll never 'shake off' the memories you made tonight."

The 26-year-old is currently in Australia with Hiddleston who is working for Thor: Ragnarok. Harris' social media claims were triggered when Swift's team allegedly took credit for Rihanna's This Is What You Came For. It was revealed that Swift helped in the song's creation and only used the pseudonym Nils Sjoberg. Nonetheless, Harris said that it was him who did much of the work for the track.

Taylor and Calvin's romance gone awry [Photo by Jason Kempin/Getty Images for iHeartRadio / Turner]The DJ also confirmed something that many have been speculating about since the release of Bad Blood – that Katy Perry's indeed the one Swift was singing about. He claimed that his former girlfriend is trying to "bury him" like what she did with Perry.

Following his rant, trolls rushed to Swift's Instagram page and littered the comment section with "snake" emojis. Swifties, on the other hand, are trying to fight back by posting "heart" emojis. Harris' revelation also led to the #TaylorSwiftIsOverParty hashtag. Angered Twitter users accused Swift for being "two-faced" and for having the penchant to always "play the victim."

Perry indirectly responded to the issue by sharing a GIF of Hillary Clinton smiling and shrugging. She also reposted her 2015 tweet.

Perry and Swift's friendship started in 2008 when they appeared at the MTV Video Music Awards. They were so close that Swift gave Perry a lock of her blonde hair as a keepsake. The two also sealed the deal when they performed Hot and Cold at Swift's 2010 show in Los Angeles.

[Photo by Larry Busacca/Getty Images for NARAS]Things started getting shaky when Perry dated John Mayer, Swift's ex and the inspiration for Dear John. However, Swift told Rolling Stone that the feud wasn't about a guy.

"For years, I was never sure if we were friends or not. She would come up to me at awards shows and say something and walk away, and I would think, 'Are we friends, or did she just give me the harshest insult of my life?'"

She then revealed the reason behind the row.

"She did something so horrible. I was like, 'Oh, we're just straight-up enemies.' And it wasn't even about a guy! It had to do with business. She basically tried to sabotage an entire arena tour. She tried to hire a bunch of people out from under me. And I'm surprisingly non-confrontational – you would not believe how much I hate conflict. So now I have to avoid her. It's awkward, and I don't like it."

Swift recruited her "squad" in creating the music video for Bad Blood. In the video, Selena Gomez played the role of Swift's arch enemy and fans were quick to point out the character's similarity with Perry particularly her hairstyle.

The Teenage Dream singer stayed silent but warned people to "watch out for the Regina George in sheep's clothing" using the popular villain from Mean Girls as a reference.

[Image via Children's Health Queensland & Lady Cilento Children's Hospital, Facebook]