Sofia Coppola And Phoenix's Thomas Mars Have Baby Girl

Cosima is the couple's second child, joining 3-year-old sister Romy.

Oscar-winning director Sofia Coppola and Grammy-winning Phoenix frontman Thomas Mars have recently given birth to their second baby girl, People magazine reports.

Named Cosima, the girl was born "within the last month," a source told the magazine. The newborn is the couple's second daughter, joining Romy, who is now 3 years old. The couple began dating in 2005 and revealed that Coppola, who won a best writing Oscar for "Lost in Translation," was pregnant in December.

The duo have most recently collaborated on Coppola's upcoming film "Somewhere," with Phoenix writing what Mars has described as a "very minimal" soundtrack for the project.

"She asked us to do some music, very in the spirit of 'Love Like a Sunset,' so we tried to put that track and elements of the track in the movie, and it worked well," Phoenix guitarist Christian Mazzalai told MTV Radio. "And then we wrote very small pieces of music, very minimal music for the movie too. ... We're very proud of it."

"This is the first time we feel [that] the music fits to the picture," bassist Deck D'Arcy added. "We've [been on] many soundtracks before, and it's always weird for us — producers must like [our songs], of course, if they use them — but for us, it's always weird to see them in the films."

Starring Stephen Dorff as a Hollywood bad boy, "Somewhere" takes place largely at the famed Chateau Marmont hotel. The first trailer dropped earlier this month, with the film expected to hit theaters in December.

Mars, meanwhile, continues to tour with Phoenix, which won a Best Alternative Music Album Grammy last year. The band kicked off the latest leg of their tour June 11 in North Carolina and then headed off to Germany and the U.K. They'll weave throughout Europe before returning to the States in August and finally wrapping up in Mexico City at the end of September.

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