Sinead O’Connor, who died earlier this week at the age of 56, will always be remembered for “Nothing Compares 2 U,” her 1990 hit that was originally penned by Prince. Still, it wasn’t the only time the Irish singer recorded a song written by the Purple One.

O’Connor’s relationship with Prince was reportedly very complicated. When “Nothing Compares 2 U” became a global hit, Prince was outwardly supportive. However, behind the scenes he denounced the way O'Connor handled herself in interviews, specifically how often she cursed.

"I don't like the language you're using in your print interviews... I don't like you swearing," Prince reportedly told Irish singer one night at his house (as detailed in O'Connor's memoir Rememberings). "I don't work for you," she responded. "If you don't like it, you can fuck yourself." Later that same evening, Prince instigated a pillow fight with O'Connor, but allegedly put heavy items in his pillowcase with the intent to hurt her.

Watch Sinead O'Connor's 'Nothing Compares 2 U' Video

O’Connor maintained respect for Prince's work, but admitted she "didn't like the man." She vowed to never record another one of his songs, but decades later she relented.

Fun Lovin' Criminals drummer Frank Benbini met O’Connor sometime around 2013 at a charity gig in Dublin. At the time, Benbini was working on an album of Prince reggae covers with his side project, Radio Riddler.

"I discovered that she had a massive love for reggae music - which those that have followed her career will know," Benbini recalled to Sky News. "We just hit it off.”

Benbini asked O’Connor if she’d sing on his reggae rendition of “I Would Die 4 U.” "That was the song I always thought Sinead would sound amazing on," he explained. "I spoke to her about it and she said: 'I always vowed never to do another Prince song.' But I said I'd send it anyway."

After listening to the demo, O’Connor agreed to perform the song’s vocals. According to Benbini, the Irish singer was a pleasure to work with – a far cry from her reputation of being difficult.

“She was super humble and really funny,” the drummer recalled. “She was nothing like she'd been perceived to be over the years... there was an air of shyness about her but also an air of, she knew what she wanted, knew who she was. She didn't have any airs or graces, she was very much down to earth, which is quite rare in rock'n'roll."

Listen 'I Would Die 4 U' by Radio Riddler and Sinead O'Connor

Released in 2014, Radio Riddler’s album Purple Reggae received only minimal attention. Reviews were generally good, but it failed to find an audience with mainstream music fans. Though the response to O’Connor’s second Prince cover paled in comparison to the first, Benbini was thrilled with the result.

"She said she'd vowed she'd never cover another Prince song. But I think coming from the world of reggae... that was really what got her to do 'I Would Die 4 U,'" he explained. "It was the second time she ever did a Prince song, which I'm super proud of and it's such a beautiful version."

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