And Kelli was asked how they got into their very tight leather cat suits!
Her answer: "With a lot of talcum powder."
So now you know!
The band met massive Ali G fan Carl Wallace, 16, from Stoke
He's having treatment for a brain tumour.
Feeling like Ali G
He was wearing the trademark hat and
bright yellow tracksuit and gave Liberty X his best Ali impression.
When he was asked where Julie was he said: "She's down the West Side innit."
Not bad at all, Carl!
After having a go on the website, Liberty X went on a tour of the hospital to meet fans and were interviewed by patients for a feature on the site.