Miley Cyrus Mocks Sinead O'Connor: 'Before Amanda Bynes There Was …'

The 20-year-old responds to a highly publicized open letter, posting images of O'Connor's controversial "SNL" appearance and a string of worrisome tweets from 2012.

Miley Cyrus has received your open letter, Sinead O'Connor, with its warnings against "selling your body" for attention and profit. In response the 20-year-old pop singer, fresh off her first Hot 100 No. 1 with "Wrecking Ball," has decided to mock you.

In a blog post on her website, O'Connor told Cyrus that she was "extremely concerned for you that those around you have led you to believe, or encouraged you in your own belief, that it is in any way 'cool' to be naked and licking sledgehammers in your videos." She goes on to argue that Cyrus "will obscure your talent by allowing yourself to be pimped, whether its the music business or yourself doing the pimping."

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On Thursday morning, Cyrus responded on Twitter by calling attention to O'Connor's public meltdown of early January 2012, in which she incoherently pleaded with followers to help her find a psychiatrist. "I'm sorry worrying anyone.. is just am sick and ireland shit for finding help cant think of any other way," O'Connor wrote. On Twitter, Cyrus references another celebrity who has a history of bizarre online behavior, actress Amanda Bynes. 

(Bynes is currently at The Canyon, a rehab center in Malibu, Calif., where she is receiving psychiatric care to address mental health issues.)

O'Connor's letter urges Cyrus to not trust anyone who supports or encourages her current image as a twerking, sledgehammer-licking provocateur.

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"I repeat, you have enough talent that you don't need to let the music business make a prostitute of you," continues O'Connor. "You shouldn't let them make a fool of you either. Don't think for a moment that any of them give a flying fuck about you. They're there for the money.. we're there for the music. It has always been that way and it will always be that way. The sooner a young lady gets to know that, the sooner she can be REALLY in control."

In response to O'Connor's words about her controversial ways, Cyrus pointed to the infamous 1992 incident on Saturday Night Live when the elder singer ripped up a photo of Pope John Paul II.