Demi Lovato and Taylor Swift are cool for more than just the summer.

Case in point: Taylor danced and sang along to the Disney Channel alum's performance at the 2023 MTV Video Music Awards. As seen in an audience camera footage from the Sept. 12 ceremony, the 33-year-old—who picked up a total of nine awards that night—happily bounced around in the crowd as Demi belted out "Cool for the Summer (Rock Version)" onstage.

After a Taylor fan account posted a clip of the moment on X, formerly known as Twitter, Demi responded on Sept. 13 with three emojis of a smiling face surrounded by hearts.

The 31-year-old has known Taylor for years, having broken out into the music scene around the same time as the pop star during the late aughts.

However, rumors of beef  between the two singers emerged in 2010 after Demi gave a very blunt reply to a question about their mutual friend Selena Gomez. When a fan asked Demi about Selena, who she costarred with on Barney and Friends as kids and in 2009's Princess Protection Program, she simply answered, "Ask Taylor."  

Speculation of a feud continued to swirl in the following years, with Demi seemingly calling out Taylor for making a $250,000 donation to Kesha amid her legal battle with Dr. Luke in May 2016. At the time, Demi tweeted without naming the "Anti-Hero" artist, "Take something to Capitol Hill or actually speak out about something and then I'll be impressed."

Demi touched on her eyebrow-raising comment later that year. "Listen, there's nothing positive that comes from pitting women against each other," she told Refinery 29. "There are women that I don't get along with, and that's fine. My thing is, don't brand yourself a feminist if you don't do the work."

For four years, Demi was also managed by Scooter Braun, who butted heads with Taylor after obtaining the masters to her first six albums and prompted the pop star to re-record her music in order to own the rights. In fact, Demi defended Scooter amid his highly publicized music battle with Taylor, calling him a "good man." 

"I have dealt with bad people in this industry and Scooter is not one of them," she wrote on her Instagram Story in 2019. "Personally, I'm grateful he came into my life when he did. Please stop 'dragging' people or bullying them. There's enough hate in this world as it is."

The "Confident" singer recently parted ways with Scooter, though the two appear to remain on good terms. On her birthday Aug. 20, Scooter wrote in a message to the star on Instagram Stories, "Happy birthday to one of the kindest souls out there."

But there's still some bad blood running through Hollywood. For details on other celeb feuds, keep reading.

In September 2023, while playing a game called Stir the Pot with her daughter Kelly Osbourne on E! News, Sharon said the That '70s Show alum was the rudest celebrity she had ever met, branding him, a "rude, rude, rude, rude little boy" and a "Dastardly little thing." He did not respond to her remarks publicly.

Five years prior, Sharon told Larry King that when Ashton appeared in 2014 on The Talk, when she was a co-host of the show, he came on with an "attitude" after she got his name wrong.

Sharon continued, "He goes, 'What are you, what have you done in this industry?' And I was like, 'Kid, don't start with me, because I'm gonna eat you up and s--t you out.' So I was just like, 'You don't know what you're dealing with, kid.'"

In August 2022, Cassadee and Maren traded harsh words with Brittany, wife of fellow country star Jason Aldean, after she shared an Instagram Reel of herself applying makeup on Aug. 23, writing, "I'd really like to thank my parents for not changing my gender when I went through my tomboy phase. I love this girly life."

 

During a 2022 TikTok challenge, JoJo Siwa described Candace Cameron Bure as the "rudest" celebrity, later explaining that she felt snubbed when Bure once refused to take a picture with her on a red carpet. Shortly after the dig, however, the Full House alum apologized: "I kind of broke your 11-year-old heart. I didn't take a picture with you. Ugh! I feel crummy, I feel—JoJo, I'm so sorry."

The two made amends. But months later, Candace was asked in a Wall Street Journal interview if she expects the Great American Family network, of which she serves as chief creative officer, to feature same-sex couples as leads in holiday movies. She said no, adding, "I think that Great American Family will keep traditional marriage at the core."

JoJo, who came out as a member of the LGBTQ+ community in 2021, wrote on Instagram that the actress' comment is "rude and hurtful to a whole community of people."

In June 2021, Courtney Love accused Olivia Rodrigo of copying her band Hole's album cover for a promotional photo without giving credit. Olivia responded, "Love u and live through this sooooo much." Courtney then replied, "Olivia - you're welcome. My favorite florist is in Notting Hill, London! Dm me for deets! I look forward to reading your note [winking face emoji]."

During an appearance Watch What Happens Live, the Happy Days actor was asked why he didn't get along with the Forrest Gump star on the set of the 1989 flick Turner & Hooch.

"I was directing that movie for 13 days and then I was called into [producer] Jeff Katzenberg's office and he said, 'You have everything with you? Go home,'" he said.

Winkler did, however, seem to get along with Hanks' four-legged co-star. "I got along great, great with that dog," he said. "Love that dog."

He also refused to admit if he's even seen the flick. 

"You know what you did!"

Fans of The Hills will remember that iconic line, delivered by Lauren Conrad on the season three premiere. Their feud began when Heidi Montag started dating her now-husband, Spencer Pratt. The feud hit its peak after rumors started flying that Conrad had made a sex tape with her ex, Jason Wahler, rumors which Conrad believed Pratt and Montag started.

The Fast and Furious co-stars had been involved in an ongoing feud, which reignited when Gibson publicly called out Johnson on Instagram after the Fast and Furious 9 release date was pushed. The film was originally scheduled for release in April 2019, but the date was later pushed back to April 2020. That same day, it was announced that a Fast and Furious spinoff starring Johnson and Jason Statham would hit theaters in 2019. The following month, Gibson threatened to quit Fast 9 if Johnson was in the movie.

Gibson then opened up about the feud, telling Van Lathan on The Red Pill podcast, "I have yet to talk to The Rock to this day, and we will have a conversation." Gibson shared that he did have a conversation with Johnson's producing partner, but not the actor himself.

"I found myself being the messenger on behalf of various people associated to the franchise, but stupid me was the only one who went public about those feelings, which is my own fault," Gibson said. "It's not professional, it's not cool."

No more bad blood here.

Taylor Swift and Katy Perry had been in a feud for years, even allegedly inspiring Swift's song "Bad Blood." The drama, which reportedly started over a backup dancer and competing tours, came to an end in May after Perry sent Swift a literal olive branch before her Reputation Tour kickoff.

"So I just got to my dressing room and found this actual olive branch," Swift said in an Instagram video. "This mean so much."

Swift captioned the video, "Thank you Katy."

Sex and the City co-stars Kim Cattrrall and Sarah Jessica Parker had dodged feud rumors for years. But those rumors were reignited after Cattrall decided not to return for a third movie and made comments about her co-star that raised eyebrows.

"What was your reaction to Kim Cattrall telling Piers Morgan that you were never friends just colleagues?" Andy Cohen asked Parker on a Sept. 2017 episode of Watch What Happens Live.

As she explained, "Just...heartbroken. I mean that whole week, you and I spoke about it because I was just...I don't know I found it really upsetting because that's, you know, that's not the way I recall our experience."

"So...it's sad but I'm kind of...I don't know, I always think that what ties us together is this singular experience is the thing. It was a professional experience but it became personal because it was years and years of our lives. So I'm hoping that that sort of eclipses anything that's been recently spoken," she continued. "That many years spent doing something so special that people had a connection with is such a privileged."

The iconic singers have been feuding since 2004. While accepting the Classic Songwriter Award at the Q Awards that year, Elton John said to attendees, "Madonna, best f--king live act? F--k off! Since when has lip-syncing been live? Sorry about that, but I think everyone who lip-syncs in public on stage, when you pay like 75 quid to see them, should be shot."

Former Grey's Anatomy star Katherine Heigl sparked a feud with series creator Shonda Rhimes in 2008 when she removed her name from the Emmy Awards consideration. The actress stated that her reason for the move was because she wasn't "given the material to warrant a nomination."

Rhimes later opened up about Heigl's decision during an interview with Oprah Winfrey on Oprah's Next Chapter in 2012. "On some level it stung and on some level I was not surprised," Rhimes said. "When people show you who they are, believe them. I carry that [mantra] with me a lot. It has served me well."

It was the New York Fashion Week fight heard 'round the world. Nicki Minaj and Cardi B got into a heated altercation at the Harper's Bazaar Icon party in September. The following month, Cardi opened up about the catalyst for the fight with Nicki.

"For a while now she's been taking a lot of shots at me," Cardi said in W magazine's Art Issue. "I spoke to her twice before, and we came to an understanding. But she kept it going."

The real spark of the fight came when Cardi saw that Minaj had allegedly liked and then unliked a tweet about Cardi's parenting skills, which Minaj has denied. "I was going to make millions off my Bruno Mars tour, and I sacrificed that to stay with my daughter," Cardi continued. "I love my daughter. I'm a good-ass f--king mom. So for somebody that don't have a child to like that comment? So many people want to say that party wasn't the time or the place, but I'm not going to catch another artist in the grocery store or down the block."

Tension between Kanye West and Taylor Swift first started in 2009, when the "Stronger" rapper took the stage during Swift's acceptance speech at the MTV Video Music Awards. Years later, the two would make up and even become friends, but that came to an end after the release of West's song "Famous," in which he name-checks the "End Game" singer.

"I don't know her."

It's been over 15 years since Mariah Carey and Jennifer Lopez's "feud" has been going on. It all started when Carey was asked to give her opinion on several singers during an interview. When asked her opinion on Lopez, Carey replied, "I don't know her."

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