Amid rumors that Brad Pitt and Angelina Jolie are heading to a divorce, the "Fury" actor is reportedly cheating on his wife with Sienna Miller. Meanwhile, the "Maleficent" star is reportedly geting paranoid over the spreading allegations.

According to a report by Celebrity Dirty Laundry, Brad Pitt and Angelina Jolie, who have been facing divorce rumors since getting married last year, are facing another marital blues as the actor is rumored to be eyeing actress Sienna Miller.

Brad Pitt is currently working with the actress in the movie "The Lost City of Z," which he produced.

The two started working together on the project beginning last August and since then, Brad Pitt has allegedly always talked about Sienna Miller.

"Angelina has heard Brad bring up Sienna's name almost every day since the film went in to production in August," an insider told. "Brad told her to let him do his job as a producer, and Angelina yelled that she didn't want him near Sienna. They barely spoke to each other the next day."

Angelina Jolie is reportedly convinced that Brad Pitt has feelings for Sienna Miller that she forbid her husband to go to North Ireland where the movie is being filmed.

The report added that Angelina Jolie has all the reasons to be paranoid about Brad Pitt's alleged cheating as Sienna Miller recently broke up with Tom Sturridge.

The actress also has the reputation of being linked with co-stars while  doing their projects.

The 33-year-old actress was most recently linked with co-star Robert Pattinson, who is now engaged to girlfriend FKA Twigs, a report from News Every Day said.

Previous reports claimed that Brad Pitt and Angelina Jolie's marriage could possibly lead to divorce alleging that the "Maleficent" star has been very controlling of their relationship.

Allegedly, the actor has grown tired of Angelina Jolie's attitude while they were filming "By the Sea" as she constantly tells Brad Pitt what to do.

"By the Sea," which is set to hit the big screen later this year, is their first film together as a married couple.