The pair were said to have had a frosty relationship in the past, but Minogue has revealed that they have become closer while filming the current series of the UK talent competition.
The former Home And Away star opens up about their friendship in the latest issue of UK magazine Marie Claire.
She said: 'Cheryl's always been there for me when I've had a hard time.'
Despite not socialising outside of the show because of their hectic schedules, the 39-year-old singer said they are getting on better since she gave birth to son Ethan in July.
She said: 'Cheryl said to me the other day, 'I don't know how you're doing all this. I know how crazy it is when all the contestants are running in and out and I have no make-up on. And then I think of you trying to fit in feeding the baby as well.''
The former Australia’s Got Talent judge also revealed that she feels the days of being overshadowed by big sister Kylie seem to be over.
She said: 'Can you imagine for years being asked what it’s like to be Kylie's sister?
'I guess it's my turn now to enjoy what is going right.'