One of the things that makes Nicole Poturalski beautiful is her lips - however, it's also what causes the problem with her and Brad Pitt. 

According to the National Enquirer, Brad Pitt is worried that his "fame-hungry" girlfriend would write a tell-all or blab his secrets to other people. 

Sources told the publication that Pitt threatened Poturalski to "zip it - or we're through." 

They claimed that the 56-year-old Hollywood hunk his hit the roof after his model girlfriend spilled some juicy tidbits about their new romance. 

Now, the outlet claims that the worst is coming for Pitt as his girlfriend is reportedly mulling over a full-blown tell-all. 

"This is a nightmare for Brad. It's starting to hit him that he's bitten off more than he can chew," an insider snitched. 

"He's had an amazing time with Nicole and still finds her wildly attractive. But he's also confided a lot of intimate secrets to her that he probably shouldn't have," they added." 

Nicole Poturalski has reportedly already slipped out a couple of things, but the Enquirer's sources said there's a lot more she could divulge. 

"It's likely to become messy as hell," they added. 

The insider further added that the "Fury" star was always careful with the women he hooks up with, as he chooses only those who know how to keep their mouths shut.

"But Nicole is bragging to pals about what a great time she's having," the source revealed.

"She's going into way too much detail, especially with her bad-mouthing of Angelina and what Brad said about their custody battle."

Brad Pitt will always be worried that Nicole Poturalski will do a full sit-down interview once they split, and things would become a disaster for the "Ad Astra" actor. 

Once Pitt's secrets come out, it would only add fuel to the fire, which could make him lose in his legal battle against Angelina Jolie. 

"The last thing he needs is to give Angie any more ammunition. But Nicole's loose lips are already causing a major headache, so Brad needs to get a grip on the situation fast before it bites him in the butt any harder."

However, it is best to take the National Enquirer's claim with a grain of salt. 

Representatives of Brad Pitt and Nicole Poturlski didn't mention any tell-all interview, and no secret about the actor has been divulged for the public to know. 

Angelina Jolie, Brad Pitt courtroom showdown

The couple has been together for more than 11 years but has only been married for four. In 2016, they announced they were getting a divorce. 

Four years later, the former power couple is still not done with all of the divorce issues. 

Currently, Brad Pitt and Angelina Jolie are battling it out in the courtroom as they fight for their kids' custody.

According to reports, Brad Pitt wants joint equal custody of his six children. 

"Angie is losing her mind and will really go over the edge if she gets permanent joint custody of the kids," a source told In Touch.

Pitt and Jolie submitted a list of their witnesses, which will help determine what could happen to the kids' custody. 

Reports also said family therapists, psychologists, parenting coordinators, and even co-stars are asked to take the stand. 

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