The Celebrity Big Brother star confirmed that the former couple, who separated following the exposure of her eight-year affair with his brother Ryan Giggs, are living together again, but have not restarted an "intimate relationship".
However, the 29-year-old said that she would eventually like a sister for their son Louis, 5, and Liam, her 10-year-old child from a previous relationship.
"If we do get back together properly, it would 150% be forever. We wouldn't do it otherwise," she told Closer.
"Rhodri and I are living together again, although it's not an intimate relationship at the moment. It's early days and it's still very raw for him - but we're getting on really well."
She added: "I've always wanted a little girl. If I had another boy, I'd want to try again until I had a girl, like Victoria Beckham."
Natasha accepted, though, that Rhodri is "still very hurt" by the affair and will need time to consider their relationship.
"It's a huge thing for Rhodri to get over - especially as everyone will always have an opinion," she said. "It's hard for us to move forward.
Natasha was last month forced to deny rumours that the couple are renewing their vows after they were spotted walking arm in arm.
The full interview appears in the new issue of Closer magazine, out now.
> Ryan Giggs's brother Rhodri: 'He's a cheating worm who ruined my life'