Nicole Richie and and Joel Madden at Bondi Beach in Sydney, Australia. April 3, 2007.
Beetham/Hammond/Splash News

A year ago Hollywood bad girl Nicole Richie and Bible-reading rocker Joel Madden would’ve seemed like an odd match.

But those close to the couple – who are expecting a child together this winter – say that it was only a matter of time before the two got together.

As friends of the couple tell Us, Richie, 25, and Madden had circled each other for years, but did not officially meet until mutual friends introduced them at an event in late 2006.

The two started an e-mail friendship – and when Madden split with singer Hilary Duff, 19, Richie made a move.

“Nicole pursued him,” says a source. “She said she liked how he was a ‘good mama’s boy’ in a bad boy body.”

Soon, the pair started going on dates around L.A., including a lunch at the Polo Lounge on December 3. By January, they were an item. After her DUI arrest (a “wake-up call,” for both of them, says the source), Madden asked her to trade her nightlife adventures for nights in.

Madden, 28, who grew up praying at Calvary Gospel Church in Waldorf, Maryland, and has a Sacred Heart (among other religious tattoos) on his forearm, has proven to be the stabilizing force the Simple Life star desperately needed. He even recites Bible passages to his girlfriend on a regular basis.

“Joel tamed her,” says a source close to the couple. “He took her from that dark path she was heading toward and turned her around into a truly responsible person.”

Adds a mutual friend of the couple, “Nicole brought out his fun-loving side, and he domesticated her.”

For more details on Nicole and Joel’s relationship and how they’re preparing for their first child, check out the new issue of Us Weekly, on newsstands this week.

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