Sinead O'Connor, Miley Cyrus Sinead O'Connor, Miley Cyrus

Sinead O'Connor isn't finished with Miley Cyrus just yet.

O'Connor posted three more letters to Cyrus on Facebook in response to the "Wrecking Ball" singer comparing O'Connor to Amanda Bynes,posting old tweets of O'Connor seeking a psychiatrist and a photo of her infamously ripping up a photo of the Pope on Saturday Night Live in 1992.

"Who the f--- is advising you? Because taking me on is even more f---in' stupid than behaving like a prostitute and calling it feminism," O'Connorwrote. "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."

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O'Connor angrily explained to Cyrus that mocking people for mental illness is dangerous, and even goes so far as to threaten that Cyrus will "one day suffer such illness, that is without doubt."

"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 t--s out to read, "O'Connorexplained.

Cyrus brushed off O'Connor's comments on Twitter, writing, "Sinead. I don't have time to write you an open letter cause Im hosting & performing on SNL this week. So if youd like to meet up and talk lemme know in your next letter. :)"

O'Connor once again took to Facebook in response, telling Cyrus, "I have no interest whatsoever in meeting you," adding that hosting SNL"is a bullshit reason" for not doing the right thing.

"You can take five minutes today between g- string fuckin' changes to publicly apologise and remove your abusive tweets. If you do not then you don't give a shit who you mock and what damage you do by being so ignorant," O'Connor continued. "When you publicly apologise to Amanda and myself and all mental health sufferers as well as all who were abused by priests that will end the matter as far as I am concerned."

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O'Connor also pointed out the hypocrisy in Cyrus' decision to make light of Bynes' current mental health issues by comparing her plight to that of Cyrus' friend and Bangerz collaborator Britney Spears. "If [Spears] is your friend and more importantly if you are a true friend to her.. you ought apologise for joining those who mock and humiliate women who have been too nice frankly, to manage the music business without sensibly losing their minds," O'Connor said.

The Irish singer repeatedly threatened legal action against Cyrus if the tweets are not removed, claiming they have created a false image of mental instability which will hurt her career "since it is extremely hard to be given work when people think one is suffering from mental illness."