Pax, 19, called his world-famous dad, 59, a ‘world-class a**hole’ and a ‘f*****g awful human being’ in a 2020 post.
Across a photo of Brad collecting his Oscar for Once Upon a Time… in Hollywood, Pax wrote on Father’s Day that year: ‘Happy Father’s Day to this world-class a**hole.
‘You time and time again prove yourself to be a terrible and despicable person.’
In the post, unearthed by MailOnline, Pax went on: ‘You have no consideration or empathy towards your four youngest children who tremble in fear when in your presence.
‘You will never understand the damage you have done to my family because you are incapable of doing so.’
Pax concluded: ‘You have made the lives of those closest to me a constant hell. You may tell yourself and the world whatever you want but the truth will come to light someday.
‘So Happy Father’s Day, you f*****g awful human being.’
A source told the outlet that the account is Pax’s, saying: ‘It’s the account he uses for friends – friends from school mostly. He never says much about his parents, keeps himself to himself, so that was unusual.’
Pax’s mum Angelina, 48, adopted him from a Vietnamese orphanage in 2007 with Brad formally adopting him a year later.
His parents were together for 12 years before splitting in 2016 and also share Maddox, 22, Zahara, 18, Shiloh, 17, and twins Vivienne and Knox, 15.
Brad and Angelina met in 2005 on the set of Mr. and Mrs. Smith and since their split have been embroiled in various legal disputes.
Most recently, the former couple were locked in a huge battle over their Chateau Miraval estate after the Maleficent actress sold her share.
Brad and Pax’s relationship is thought to have been fraught since 2016.
In September of that year, the Jolie-Pitt family was flying from France to LAX on a private jet, a journey which the FBI investigated.
The bureau became involved after receiving an anonymous tip claiming Brad had ‘verbally and physically assaulted’ his then-wife and their children on the flight.
It was later revealed the tip came from Angelina.
Police and social services in Los Angeles were also reported to be involved and investigating the allegations.
However the case was dropped and he was cleared of any wrongdoing, with Brad denying all accusations at the time.
A statement from the FBI read: ‘In response to allegations made following a flight within the special aircraft jurisdiction of the United States which landed in Los Angeles carrying Mr Brad Pitt and his children, the FBI has conducted a review of the circumstances and will not pursue further investigation.
‘No charges have been filed in this matter.’
Metro.co.uk has reached out to Brad’s reps for comment.
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