"I think the most important thing is to be a grownup," she says, "and not let any kind of feelings affect how you deal with your children."
For the mother-of-two – who finalized her divorce from Ryan Phillippe in June – that means having "a lot of communication" with her ex-husband and "just being very open."
"I'm very lucky in that we raise our kids to just be happy," the actress, 32, said Sunday in Beverly Hills while promoting her film Four Christmases – a comedy that focuses on the challenges of blended families. "I think the most important thing is the children. What do they want, what makes them feel comfortable?"
Parenting SkillsIn the film, Witherspoon plays the daughter of divorced parents who, at first, lacks any parenting skills. Could Witherspoon relate?
"When I first held my baby, Ava, [that] was the first time I'd ever held a baby in my life," she said. "So I understand that sort of fear or not being a good mom. It took me a long time to feel really comfortable in the role of being a mother." (In addition to Ava, now 9, Witherspoon and Phillippe also have a son, Deacon, 5.)
As for marriage, "I [had] a certain idea what I thought marriage gives," says the actress – who's now dating Jake Gyllenhaal, 27. But "sometimes it doesn't work out that way so you have to be open to whatever comes your way in life. … Love and relationships take all kinds of shapes and it's not necessarily the ones you recognize."
So, would she ever get married again? "I don't know," she says, laughing. "I don't think about it much."
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2007: Reese & Ryan move on with costars