Nile Rodgers found Joni Sledge's death "heartbreaking".
The 64-year-old star co-wrote and co-produced Sister Sledge's 1979 breakthrough album 'We Are Family' and has admitted to being devastated by the recent passing of Joni, who died from natural causes on March 10 at the age of 60.
He shared: "It's really heartbreaking. To me, they always felt like our younger sisters. How can they die before us, you know?"
Nile said Joni's outspoken nature marked her out as being different from her sisters, Debbie, Kim and Kathy.
He told Billboard: "She was sort of like the leader of the group, the most outspoken.
"Even though Kathy had that magical voice, Joni was the one who, when you ask a question she's the one who gives the answer, 'cause all four people can't speak. It would be a cacophony."
What's more, Nile revealed he still considers the 'We Are Family' album to be "the best record I ever made" - even though he has worked with some of the biggest-selling artists in history.
He explained: "That was the record that proved [Chic] could do what we do for ourselves for others, that we could look inside someone's soul and put our version of their truth onto them and superimpose it onto them and create this new entity we believed we understood.
"There's no filler on Sister Sledge; Every song is awesome. It was a record that was really incredible to us."
Meanwhile, Nile is currently putting the finishing touches to 'It's About Time', his first Chic album in 25 years - and he's told fans they can expect to hear it "soon".
The music icon - who co-founded the band with Bernard Edwards - said: "It hit me that 2017 was the 40th anniversary of Studio 54 and the 40th anniversary of Chic. We started together.
"So I'm thinking that's a good omen for putting this thing out soon."
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