There didn’t seem to be any tension between them — until now! On Aug. 1, Jennifer Garner was spotted walking in Brentwood with estranged husband Ben Affleck‘s mom, Christine Boldt. The pair flashed big smiles as they strolled down the sidewalk arm-in-arm, shared a pair of sunglasses, and even embraced repeatedly. “It was weird to see them being so chummy,” an insider told In Touch exclusively, “because Ben has put Jen through so much.”

And now she’s gearing up to put him through a rough time. Four months after filing for divorce to end their nearly 12-year marriage, Jen, 45, is making a power move: She’s going after a larger chunk of Ben’s money as their split moves forward and his net worth, estimated at $105 million, continues to grow. “The fight over money is going to get nasty,” said the insider. Jen, whose net worth is a reported $60 million, endured so much in the final days of their marriage. Not only did a nanny cheating scandal erupt mere weeks after they announced their split in 2015, but this summer, Jen had to suffer the public humiliation that came with the news that Ben’s current girlfriend, Saturday Night Live producer Lindsay Shookus, has actually been in the picture for many years. “For all of this and more,” said the insider, “Jen has made the decision to go after Ben’s future earnings.”

MORE: Jennifer Garner Is So Done With Ben Affleck and His Childish Ways (EXCLUSIVE)

ben affleck jennifer garner

Ben and Jen during happier times at the Critics’ Choice Movie Awards in January 2011.

Not to mention, women have to worry about getting fewer and fewer roles as they get older in Hollywood, said the source, but that’s often not the case with men. Ben, 45, “will continue to earn top dollar and is still being offered the best movie roles. Despite all his personal problems, he’s more in demand than ever.” Jen knows it, too. After years of making sacrifices for the sake of her troubled ex — who completed rehab for alcohol addiction in March — Jen is formulating a plan to get what she deserves. “She’s been reaching out to top Hollywood divorce attorneys. She wanted the split to be amicable,” explained the source. “But she needs a pit bull who isn’t intimidated by Ben’s power and wealth and who will be relentless in getting her the biggest divorce settlement possible.”

MORE: Ben Affleck Wants to Have a Baby With His New Girlfriend, Lindsay Shookus (EXCLUSIVE)

Her chances are good, especially when it comes to getting a cut of the Batman franchise. “If Ben signed a contract to do a movie while they were still married, then, yes, she has a right to a part of the money he’s going to get from that movie because it’s a community property asset,” California-based law attorney Goldie Schon told In Touch. Ben won’t know what hit him. “I imagine Ben never expected Jen to go after his future earnings, and he will absolutely be furious about it and want to fight her on it,” said the source. However, it could be a losing cause. “Ben and Jen didn’t have a prenup when they married [in 2005], so he might want to consider giving Jen what she is asking for to avoid an even heftier payoff if this goes to trial.” RIP, Bennifer!

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