The 43-year-old singer is in the girl group with Melanie Blatt, Shaznay Lewis and her older sibling Natalie Appleton, 45, and although she loves having her sister in the group the pair are not always totally on the same page.
Speaking on 'The Ken Bruce Show' on BBC Radio 2, she said: ''They all get me. Sometimes the other two get me more than my actual sister.
''But having my sis in my band, it's the best thing in the world. In fact, they all feel like my sisters, to be fair.''
A profound appreciation for music runs in the Appleton family and it was Nicole and Natalie's father Ken who instilled their love of singing and performing because he introduced them to so much great music.
Nicole - who was previously married to Liam Gallagher - added: ''My dad was always into Nat King Cole and The Andrews Sisters. And my mom [Mary] was into Barry Manilow. We learnt all that as we were growing up.''
''I was also the youngest of four, so I had my eldest sisters listening to quite old school 70s rock, like Kiss, so I kind of learnt a lot of music growing up and then developed my own sort of favourites and likes. I've got a broad spectrum of music I like ... I like anything that's really good.''
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