Since Brad Pitt and Angelina Jolie announced their divorce just hours ago, there has already been speculation that the reason is Brad Pitt's affair with Marion Cotillard.
However a source has told PEOPLE that this is not the case, and that it has nothing to do with Cotillard.
Brad Pitt and Marion Cotillard co-star in the upcoming film Allied, a World War II drama.
The New York Post has disputed this, with a source claiming that marital issues came about when Angelina Jolie hired a 'private eye' to watch the pair.
The New York Post source said, "She hired a private eye because she felt that he was fooling around with her on the set, and it turns out, he was. And that was the final straw." PEOPLE's source does not agree with this.
Angelina's estranged father Jon Voight has also commented that it was a strange decision for Angelina to make, so something big must have happened.
"Something very serious must have happened for Angie to make a decision like this," he said, according to Inside Edition. "I don’t know what it is. It’s a sad thing. Say a little prayer."