El 4: Miley Cyrus Hits Back at Sinead O'Connor in Social Media Spat

Miley Cyrus fired back at "Nothing Compares 2U" singer Sinéad O'Connor on Twitter after O'Connor penned a lengthy and motherly open letter to the provocative 20-year-old.

In the letter, O'Connor claimed that Cyrus is being "prostituted" by the music industry and predicted the former Hannah Montana star would eventually land in rehab.

Cyrus didn't take kindly to the advice. She responded with a tweet that poked fun at O'Connor's 2011 brush with mental health issues. The tweet says, "Before Amanda Bynes.... There was...." and links to O'Connor's old tweets. Cyrus followed up that tweet with a photo of O'Connor's memorable moment in which she tore up a photo of Pope John Paul II:

Before Amanda Bynes.... There was.... pic.twitter.com/6JZPVnunPc

— Miley Ray Cyrus (@MileyCyrus) October 3, 2013

#SNL pic.twitter.com/6Cq9pewEO0

— Miley Ray Cyrus (@MileyCyrus) October 3, 2013

What's the connection between Cyrus and O'Connor? Both have had No. 1 songs on Billboard's Hot 100 singles chart — but more than 20 years apart? Cyrus' "Wrecking Ball" video is reminiscent of O'Connor's "Nothing Compares 2 U" video. Cyrus has acknowledged the similarities.

Not one to back down, O'Connor addressed Cyrus' jab in a Facebook post:

Miley… Really? Who the fuck is advising you? Because taking me on is even more fuckin' stupid than behaving like a prostitute and calling it feminism. You have posted today tweets of mine which are two years old, which were posted by me when I was unwell and seeking help so as to make them look like they are recent. In doing so you mock myself and Amanda Bynes for having suffered with mental health issues and for having sought help. I mean really really… who advises you? have you any idea how stupid and dangerous it is to mock people for suffering illness? You will yourself one day suffer such illness, that is without doubt. The course you have set yourself upon can only end in that, trust me. I am staggered that any 20 yr old woman of the 21st century could behave in such a dangerous and irresponsible manner as to not only send the signal to young women that its ok to act like prostitutes but also to the signal that those who have suffered or do suffer mental health problems are to be mocked and have their opinions invalidated. Have you no sense of danger at all? or responsibility? Remove your tweets immediately or you will hear from my lawyers. I am certain you will be hearing from all manner of mental health advocacy groups also. It is not acceptable to mock any person for having suffered. It is most unbecoming of you to respond in such a fashion to someone who expressed care for you. And worse that you are such an anti-female tool of the anti-female music industry. I hope that you will apologise to Amanda Bynes and to any person who has been wounded by your mockery of those who have suffered. And I hope that you will wake up and understand that you in fact are a danger to women. Furthermore you posted a photo of me tearing the pope's photo .. as if to imply insanity.. by doing so all you have achieved is to expose your staggering ignorance. I suggest you read The Philadelphia Report, The Boston Report, all the reports which will illuminate for you why that action of mine remains sane and valid. By mocking it you mock every child who suffered sexual abuse at the hands of priests and had it covered by the Vatican. You could really do with educating yourself, that is if you're not too busy getting your tits out to read.

O'Connor continued the conversation in another Facebook post, mentioning legal action:

Ms Cyrus has today posted tweets of mine which are two years old and which were sent when I was ill and seeking medical help. She has done this in an attempt to deliberately cause me harm and hurt. I wish to confirm that I am quite well and kindly request people cease e mailing me in the mistaken belief these are recent tweets. Ms Cyrus' lawyers will be contacted by mine regarding this matter. I confirm also that I do not at all support or condone the abuse or mockery of those who have been brave enough to openly discuss mental health issues. Mockery causes deaths. Period. It is an unacceptable form of bullying, no matter who it is doing the bullying.

Cyrus then issued two more tweets, seemingly making fun of O'Connor's long letters with a reference to her Oct. 5 hosting-and-performing gig on Saturday Night Live this week:

Sinead. I don't have time to write you an open letter cause Im hosting & performing on SNL this week.

— Miley Ray Cyrus (@MileyCyrus) October 3, 2013

So if youd like to meet up and talk lemme know in your next letter. :)

— Miley Ray Cyrus (@MileyCyrus) October 3, 2013

To read O'Connor's open letter that started this public beef, click here.

This online spat is just one in a historic list of celebrity showdowns on social media. Here, for comparison, are a few more:

1. Amanda Bynes vs. Rihanna

Looking for a way to amp up the drama, Amanda Bynes took her Twitter sass to a whole new level in May with a seemingly unwarranted attack on pop star Rihanna and Chrissy Teigen of Sports Illustrated fame, calling both stars ugly. In one particularly notable moment, the former child star suggested Chris Brown's 2009 abuse of Rihanna was a result of her being "not pretty enough." Ms. Bynes, that is a new low.

2. Alec Baldwin vs. George Stark

Alec Baldwin quit Twitter again this summer following an article by journalist George Stark of the Daily Mail. The piece falsely accused Baldwin's pregnant wife, Hilaria Thomas, of tweeting during the funeral of James Gandolfini. The rant is still causing a stir for the 30 Rock star, as conservative activists demand that Capital One drop him as a spokesperson due to the homophobic nature of his tweets. Baldwin has since apologized for his language but not for defending his wife.

3. Directioners vs. British GQ

Hell hath no fury like a fandom scorned. British GQ got a taste of that hell when the magazine released its One Direction covers in July. The tagline under Harry Styles' cover, "He's up all night to get lucky," evoked such rage from Directioners that GQ's servers couldn't handle the influx of hate tweets.

4. Perez Hilton vs. Amanda Bynes

It was only a matter of time before these two butted heads. After Hilton posted a photo from an alleged eyewitness who spotted Bynes jumping on a trampoline, Bynes replied with her usual onslaught of "ugly" tweets. Eventually, Bynes insisted Hilton commit suicide. No stranger to death threats, Hilton expressed his concern for Bynes and his hope that she receive treatment.

On May 31, Bynes eventually retracted her statements about the blogger, saying, "you're not ugly! I was lying because we haven't talked in person in a long time. Please stop being mean on twitter! Thx!"

How nice.

5. Perez Hilton vs. will.i.am

In one of the most famous Twitter feuds of all time, Perez Hilton ended up with a black eye after calling will.i.am of the Black Eyed Peas a "f***cking f*ggot." While it's unclear who exactly gave Hilton the shiner, will.i.am posted a vlog insisting it was not him. Regardless who actually threw the punch, Hilton took to Twitter to seek help from the police. You know, because 911 is too old school.

6. Perez Hilton vs. Lady Gaga

In a more recent Twitter feud, Hilton found himself on the wrong side of Lady Gaga's little monsters when he was seen in the lobby of Gaga's apartment building in New York. Gaga accused Hilton of stalking her, despite his insistence it was nothing more than innocent house-hunting. Gaga's fans also let their claws out, voicing death threats and derogatory comments about Hilton's six-month-old son.

Hilton, who was once friends with the pop star, insisted that the "real" Lady Gaga was different than her public persona, calling her "cruel" and insisting he was "still healing, removing your knife from my heart" after the two's apparent fallout.

7. Rob Kardashian vs. Rita Ora

Plenty of celebs take to tweeting after a breakup, but it's hard to beat a Kardashian when it comes to drama. Rob K took to the Twittersphere to bash ex Rita Ora, saying she cheated on him with no less than 20 other men. While Ora remained mostly silent on the subject, one errant tweet did surface before it was quickly erased: "Rob's d--k was wack, I had to go get it somewhere else."

Kardashian didn't take kindly to the insult, hinting he had gotten Ora pregnant. That exchanged remained on the site only briefly before it was taken down.

One party who did remain positive throughout the feud? Rob's sister Khloe, who offered some advice: "Cheaters never prosper @RobKardashian ill be home today... Try and smile little brother."

8. Chris Brown vs. Jenny Johnson

While Chris Brown was no one's favorite person after the abuse scandal surrounding girlfriend Rihanna, one comedienne in particular, Texas-based writer Jenny Johnson, wanted to let the R&B singer know just how she felt about him. A little bit of harassment went a long way, and it didn't take too long for Brown to delete his account, but not before he tweeted: "Just ask Rihanna if she mad??????"

Brown's account has since been reactivated.

9. Rhianna vs. Chris Brown

Now that Brown has returned to Twitter, fans can follow his breakup drama with on-again, off-again girlfriend Rihanna. The tumultuous trainwreck that is the Rihanna/Chris Brown relationship just won't go away, with the breakup feud continuing through August.

RiRi tweeted an image bearing the words "If I drop all my hoes for you and we still don't work out you owe me some hoes." While the sentiment seems pretty clear, Brown's "She's not mine if she's everybody else's" tweet definitely left no room for doubt about the reason for the pair's latest breakup.

10. Nick Cannon vs. Chelsea Handler

After the acid-tongued Handler jabbed Cannon's comedy tour, saying: "I just heard nick cannon is starting a comedy tour. Who's going to do the comedy?" Cannon was clearly a little peeved at the tweet, but didn't really let loose until Handler posted a TwitPic of grape soda with the tweet "pls drink this before you tweet me again." It was at this point that Cannon wilded out (sorry not sorry for that one), letting loose the slew of angry tweets (plus a few more) that you see above.

BONUS: Patton Oswalt vs. John Tesh

Leave it to Internet favorite Patton Oswalt to create one of the punniest feuds on this list. When radio host John Tesh sent out a request for new hashtag ideas, Patton Oswalt gave a couple of suggestions, none of which seemed up to Tesh's high standards. Read the full conversation here.

Images: Fred Tanneau/Getty Images; Ethan Miller/Getty Images