Michael Jackson's grown-up son, Bigi, 22, goes head to head with grandmother, 93, in court battle

Michael Jackson's son Bigi is facing off against his grandmother, Katherine Jackson, in the latest legal drama for the famous family. 

The 22-year-old - formerly known as Blanket - has filed to stop his grandma from spending the late King of Pop's estate funds amid their legal battle.

In documents obtained by TMZ this week, Bigi is trying to block Katherine from using money from his late father's estate to fund an appeal on a previous ruling in the complex fight. 

Bigi and Katherine have been on the same page until now as they try to stop the executors of Michael's estate from making a costly transaction. 

While the case has been shrouded in secrecy, it was reported that the deal they were opposing was the sale of Michael's music catalogue to Sony for $600 million. 

© Kevin Winter

It appears that Katherine is eager to appeal the decision but Bigi sees the legal issue as closed and doesn't want further funds or money from the estate - to which he is an heir - being used to fight it. 

Bigi also asked the court that they "use its best judgment" to grant Katherine reasonable attorney fees which have been incurred during the process.

© Getty Images

Bigi's move comes a week after he was photographed in Los Angeles enjoying a solo outing to the movies. 

He turned heads with his statuesque appearance in sports shorts and a casual t-shirt, no longer the small, shy boy who was only seven when his famous father died. 

© Brian Prahl / SplashNews.com

While Bigi prefers a life away from the limelight, he has carved out a career in the entertainment industry, as a film and documentary maker. 

Bigi recently won the Best Drama award at the Santa Monica Film Festival for his work on Rochelles. He took on the role of director and screenwriter.

© Getty

As for his siblings, Paris, 25, and Prince, 27, they too have gone on to have success. 

Paris is a model, actress and singer, and Prince has dabbled in acting, producing and hosting.

The "Beat It" hitmaker died on June 25 2009 from a cardiac arrest caused by a lethal combination of sedatives and anaesthetic propofol. 

At the time, guardianship of his three children was given to his mom unless she was unable or unwilling to care for them in which case they would go to singer, Diana Ross. 

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