Olivia Wilde says her "family is everything."

The 30-year-old actress said: "Family is everything. I've always felt that way, but having a baby this year really drove that truism home."

Speaking out in support of Proposition 47, a California voter initiative seeking to reduce penalty time for certain crimes, she told E! News: "Being a mother has reinforced and refined my thinking on many issues, including - believe it or not - our criminal justice system."

The brunette beauty says her own parents also "instilled, since I was a child, a commitment to critical thinking. Don't believe what you hear; explore and analyse what you encounter to

determine your own truth. This family trait has led me to not only think deeply about societal issues but also to act."

She added: "Having my son has only increased my desire to do so."

Olivia recently admitted she has no plans to marry Jason, as they are already "fully committed" to each other.

She said: "In many ways, a child is more of a commitment. We are fully committed and really happy as a family. And there's no definition of the 'normal family' anymore. Kids today are growing up with so many different definitions of family. I guess what I'm saying is that I don't feel any pressure to do it. But I think it will be really fun."