Brian Austin Green: Megan Fox Has Boosted "My Confidence"

Megan Fox is one hot -- and capable! -- stepmom.

Fox's husband Brian Austin Green has high praise indeed for her devotion to Kassius, his 8-year-old son with ex Vanessa Marcil.

"[Megan] is absolutely my better half in parenting," Green, 37, says of Fox, 24, in the October issue of Details. "She just gets it. It's instinctual for her."

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Kassius was reportedly one of the few attendees at the couple's hush-hush wedding in Hawaii this past June. Fox called herself "really maternal" in the March issue of W magazine, and shares a home with Green and the little boy.

The actors began dating about six years ago -- when Fox was just 18, and he was 31. "When we met, I had just separated from Kash's mom and a relationship was the last thing on my mind, " Green tells the magazine. "It's not something I ever thought would be serious. But she brought out parts of me that I had lost in my last relationship. I had come off of 90210, and I never wanted to leave my house. I was afraid of the press. I was afraid of people's opinions of me," he confides. "Megan was a big part of boosting my confidence. And at the same time, I was somebody responsible and grounded for her to be around. We just matched."

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And despite her then-tender age, Fox "stepped in and took control," Green marvels. "It's unbelievable. At 18, I was like, 'Hey, which club is open tonight? And how cool do my pants look? Can I sneak a drink across the bar without getting caught?'"

The actors dated for about six years before tying the knot, and Green shoots down talk that the relationship was on again/off again, or that they ever saw other people during that time.

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"We've been together for six years," Green says. "Find a picture of one of us with any other boyfriend or girlfriend‚ I challenge you. You'll only find pictures of her doing press with Shia LaBeouf or me with my son. That's it. We never once dated anyone else or did anything else."

Green -- who next stars as a hunky, shirtless contractor on the new season of Desperate Housewives -- also tells Details that he's fine with his wife's worldwide fame, which has easily eclipsed his own.

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"I know the normal male thing is the man works and is successful and brings home the paycheck. I don't know who the hell set it up, but it’s what people expect," he quips.

"I just don't care. F**k, next year I could book some crazy movie that blows up and things could shift completely. And I guarantee you at that point she’ll say, F**k, thank God. You go do all that shit now. I'm sick of it."