• Megan Fox has reached her "breaking point" with ex Brian Austin Green, a report says
  • Fox slammed Green for posting a photo of him and their son on Instagram
  • She accused her ex-husband of making her look like an "absent mother" on social media

Megan Fox recently lambasted estranged husband Brian Austin Green over an Instagram post, leaving fans shocked. However, a new report says the outburst was a long time coming and the actress was finally fed up with his behavior.

An unnamed source told E! News that tension between the exes has been brewing for some time now, but the breaking point came when Fox “had enough of Brian’s games.” The insider said the “Jennifer’s Body” star was angry that he was trying to give her a bad image, something that the actress also mentioned in her tirade on Green's Halloween post.

"She is incredibly frustrated that he's trying to make her look like a bad mom and decided to call him out on it. She especially hates that he's using the kids to try and get back at her," the source claimed.

The tipster further explained that Green remains “bitter” that their relationship ended so he is "constantly trying to get under her skin” to get her reaction and attention. Although they could have settled things away from the public eye, the insider said that Fox felt she needed to speak up.

"She feels like he crossed a line and that something needed to be said publicly so that maybe he will think about what he's doing," the source added.

A People source echoed this sentiment, explaining that the ex-lovers have been “struggling to get along and have been for a while.” The insider also claimed that Green has been having a hard time coping with Fox's relationship with Machine Gun Kelly.

“It's a tough situation. As a dad, Brian is great. He is wonderful with the boys,” the source said, adding that it was tough for Green to see Fox moving on so “quickly.”

“His behavior can be pretty immature when it comes to Megan though. He knows how to get Megan upset. In the past, he was advised to chill out and just focus on doing the right thing for the boys,” the insider added.

Fox recently slammed the “Beverly Hills, 90210” actor for sharing a picture of him and their son Journey on Instagram. She accused Green of “feeding the pervasive narrative that I'm an absent mother, and you are the perennial, eternally dedicated dad of the year.”

Green did not directly respond to her comment but took down the snap of their son and reuploaded a solo photo.