Angelina Jolie and Brad Pitt Fight: Flirty Relationships With 'Unbroken' Actor Miyavi, 'By the Sea' Co-Star Melanie Laurent – Reports

Angelina Jolie and Brad Pitt's alleged Sydney hotel balcony fight has brought out theories and rumours on what has caused the fight. The two leading reasons of their argument are their questionable relationships with Angelina's "Unbroken" star Miyavi, and their "By the Sea" co-star Melanie Laurent, according to tabloids.

The newly married couple was photographed in what appeared to be a tense conversation just hours before they were due to attend the red carpet premiere of "Unbroken" in Sydney. According to Woman's Day magazine, the parents of six were having a "blazing argument," which could perhaps be about Angelina's full schedule.

Read: Angelina Jolie, Brad Pitt Photographed Fighting Before 'Unbroken' Sydney Premiere – Report

Since the photos have made their way online, various gossip rags have surmised what has prompted the couple to butt heads with each other. And as typical of rumours surrounding the Brangelina brand, the causes of their fight allegedly include their more-than-friends/co-workers relationship with their co-stars.

According to the National Enquirer, Brad was jealous of Angelina's closeness with Miyavi, the Japanese singer-turned-actor who plays the sadistic army sergeant Mutsuhiro Watanabe in "Unbroken." Angie and Miyavi, 33, apparently got a bit touchy-feely with each other even in Brad's presence at the film's photo call in Sydney.

"Angie and Miyavi were laughing and hugging almost every chance they got!" a source claimed to the paper, adding that it was apparent to Brad that his wife and the younger actor had a "very special bond. "I've never seen Angie act like that. It's little wonder that Brad was so jealous."

Brad's jealousy didn't just develop overnight. The tabloid added that he wasn't also thrilled when Angelina courted Miyavi for the film role because Miyavi looks like Jenny Shimizu, Angie's former lesbian girlfriend.

Miyavi and his wife and kids recently moved to Los Angeles to pursue a U.S. music career. This also didn't sit well with Brad since this would just encourage his friendship with Angelina, who thought her husband was "silly" for thinking there was something more going on with her and Miyavi.

Star magazine, on the other hand, has a different version of the Brangelina's cause of fight. It's not Brad who was jealous, but Angie. And it's not because of Miyavi, but because of Melanie Laurent, their co-star in their upcoming film "By the Sea."

"While Angelina did cast her in the movie, sources say she's been regretting her decision," an insider claimed. The source added that the 39-year-old Oscar winner is "increasingly jealous" of Brad's friendship with the 31-year-old French actress.

Melanie was also Brad's co-star in the Quentin Tarantino film "Inglourious Basterds."

Also, Brad was "sick of bearing the brunt" of Angelina's stress. Angelina has had a lot on her plate lately. If she wasn't filming, she was out to save the world through her U.N. efforts. Brad understood the stress his wife was suffering from, but he wanted her to figure out her priorities. He was also urging her to get mentally and physically healthy.

Brad and Angelina have so far kept quiet about what really happened on the balcony of their Australian hotel. Angelina recently told ITV that there's nothing bad about being married to Brad. She called him a great man, but he's still just human.

Read: Angelina Jolie Attends 'Unbroken' UK Premiere Without Brad Pitt Amid Fighting Rumours