Angelina Jolie got her sons to block the door of her rehearsal room when she was training to sing like Maria Callas

She said at the Venice Film Festival where she is promoting the movie about her nerves over the role: "Everybody here knows I was terribly nervous about the singing. I spent almost seven months training because when you work with (director) Pablo (Larrain) you can't do anything by half.

"He demands in a most wonderful way that that you really do the work and really learn and train.

"My first time singing I was so nervous that my sons were there and they helped to block the door so that nobody else was coming in.

"And I was shaky. Pablo in his decency started me in a small room and ended me in La Scala.

"So he gave me a time to grow. I was frightened to live up to her and you know I had not sung in public."

Angelina plays Maria when the singing icon was nearing death and losing her voice.

The opera legend is still idolised as the greatest voice in the history of opera and died in 1977 aged 53 after a spell of illness and isolation.

Angelina's gruelling role comes as she continues to battle her 'Fight Club' ex-husband Brad Pitt, 60, over the custody of their six children and over the shares she sold in their Château Miraval winery in France.

The actress filed for divorce from 'Fight Club' actor Brad in 2016 and the pair were awarded joint custody of their kids by a judge in May 2021.

After the ruling, Angelina decided to sell her chunk of her and Brad's vineyard, which has plunged them into an epic and complex legal battle.

A source has told Page Six Brad is refusing to let go of the fight over the business as he sees it as an asset for his children.

The insider added: "It's important that people realise that Brad's motivation is to ensure that his kids can maximise the benefit of this asset.

"Once it was sold, that's no longer the case and it significantly decreased their inheritance."