In an interview with Hello!, Liz says the families are so close that the children call her M2 or 'Mummy Two'.
She also waxed lyrical in the interview about her relationship with Shane, saying that they were made for each other and 'very similar'. Liz previously had a long term relationship with Hugh Grant, and a four year marriage to Indian textile heir Arun Nayar.
She said of her new love: "I am extremely happy when I'm with Shane. We are very similar in many ways. Despite differences in our backgrounds and careers, we both come from very secure, loving homes and to me that says a lot."
Liz, who has one child of her own, 10-year-old Damian, from her short-lived relationship with American tycoon Steve Bing, says she enjoys the children all being together, and 'tries' to be the best mother she can to them all, claiming: "I love it when we're all together. I just try to be the best stepmum that I can."
The full interview is in this week's edition of Hello! magazine which is out now.
What do you think of Liz's comments?
Too soon for Shane's kids to be calling her 'Mummy 2', or the best way for the families to integrate?
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