Kimberley, who is expecting her first baby with long-term boyfriend Justin Scott, spilled the beans in her autobiography, adding that she and Cheryl are now at totally different stages in their lives.
In a new chapter added into the paperback version off A Whole Lot Of History, Kimberley reveals that she and her fellow Girls Aloud star spoke about babies after Cheryl's holiday to South Africa in February.
Kimberley writes: "Cheryl told me she'd felt relaxed and free in Cape Town. She'd been partying and having more fun then she'd had in ages. She seemed thrilled to be back to her old self.
"She said she was happy with the way things were now and that she didn't feel ready to settle down and start a family just yet. It became abundantly clear that the two of us were in totally different places."
Despite speaking about her desire to have children in the past, it's no surprise that they are not yet on the agenda for Cheryl.
In March, Cheryl confirmed that she was returning to The X Factor as a judge and, earlier this week, joined Simon Cowell, Louis Walsh and Mel B for the first auditions in Manchester.
Meanwhile, Cheryl has also been busy promoting her comeback single 'Crazy Stupid Love' and is set to perform at Capital FM's Summertime Ball this weekend.
Later this year, Cheryl is also thought to be releasing a new album and she's recently said during a Capital FM radio interview that she'd love to tour next year. Given that she's got her hands full, perhaps she's happy being aunty Cheryl to Kimberley's unborn baby for now!
Watch Cheryl's video for 'Crazy Stupid Love' here: