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Actress Marion Cotillard is pregnant, according to a new report, and several Internet muckrakers are claiming that it could be Brad Pitt's child.

It's seems far more likely, though, that her longtime partner Guillaume Canet is the father.

Closer magazine is reporting that Marion is with child and that she is due in December.

Since the father of the child isn't publicly known, tabloid editors are frothing at the mouth. On Sept. 20, it was revealed that Brad and Angelia Jolie are divorcing. Almost immediately, several unconfirmed reports claimed that Brad had cheated on her with Marion, whom he stars with in the upcoming movie "Allied."

Marion has a 5-year-old son with Guillaume, a French actor/director. They've dated since 2007 and were photographed together last week in France.

Recently she attended the Toronto Film Festival, wearing a bump-hiding dress.

If she is, indeed, pregnant and due in December, that would put the conception date around March. At that time, she was in London with Brad filming their movie. Page Six even reported that Angelina hired an investigator who allegedly discovered evidence Brad had an affair with Marion on the set.

In April, there was some speculation that the two were carrying on an affair, but those reports caught little traction. However, the film's director, Graham King, couldn't help but notice the chemistry between the two stars.

"Brad and Marion immediately had the utmost respect for each other, so once they delved into their characters, their chemistry was electric," he told People magazine.

According to X17, Angie was unhappy with the sex scenes in the film.

"Angie couldn't handle Brad's sex scenes with Marion," the site quoted a source. "Her jealousy was out of control. Brad tried for months to reassure her and calm her anxiety, but it simply didn't work. She said her intuition was telling her he was cheating."

The source continued, "Angie has struggled with insecurity over Brad's fidelity for years, but she was never as jealous over a co-star as she was with Marion. She was always paranoid Brad would do to her the same thing he did to [his ex-wife Jennifer Aniston.]"

After news of the divorce was revealed, Brad released a statement via People, saying, "I am very saddened by this, but what matters most now is the well-being of our kids. I kindly ask the press to give them the space they deserve during this challenging time."