Michael Jackson’s son has stopped talking after Leaving Neverland, the damning documentary on his father, was released last week.

According to close family members, the 17-year-old Blanket Jackson, also known as Biji, has stopped speaking following the airing of the HBO documentary, which resurfaced allegations of child sex abuse against his father Michael.

The four-hour doco came 10 years after the pop star's death in 2009.

“Biji is the most talkative kid at school and he isn’t talking anymore,” Michael’s 45-year-old nephew Taj told the Victoria Derbyshire TV show on Friday. “We’re all worried about him.”

Blanket’s godfather Mark Lester also voiced his concern for Michael’s youngest son. 

“They try and shield him from the outside world, which may be not such a good thing,” Lester told The Sun. “Shield them from certain things, certainly, but to keep him isolated is not right.”

Lester said Blanket’s life today is tightly controlled.

Michael Jackson's children, Prince Jackson, Blanket Jackson and Paris Jackson in October 2011

“The Jackson estate don’t want him to make money for anyone else. He’s an heir to a billion-dollar trust.

“They have trust issues, especially with people who may think they want to take advantage of either Blanket, [Blanket’s older siblings] Paris or Prince for their own financial gain.

“When you get super-wealthy you become very guarded and very mistrustful of a lot of people. It’s just sad that this money issue would get in the way of them actually being able to have good friends.”

Meanwhile, Blanket’s 20-year-old sister Paris has spoken up in the wake of the documentary. 

“Injustices are frustrating and it’s easy to get worked up,” she wrote on Twitter. 

“But reacting with a calm mind usually is more logical than acting out of rage.”

Leaving Neverland, which was released for wide public viewing earlier this month, told the experiences of two men, Wade Robson and James Safechuck, who allege that the pop star sexually abused them when they were children.

Last month, the Jackson estate filed a lawsuit against HBO for “[disparaging] Jackson’s legacy by airing a one-sided hit piece against Jackson based exclusively on the false accounts of two proven, serial perjurers.” 

The lawsuit could see the Jackson estate awarded with US$100 million.

Many of Michael’s family members have spoken up in defence of the late singer. In a February interview with CBS This Morning, Taj said he did not find Michael’s “sleepovers” with young boys “odd”.

“To the outside world, yes, I think it can be odd,” said Taj. 

“I mean, I’m not oblivious to what it sounds like. But when you’re actually there in that atmosphere and you’re around it, and you’re watching movies with his kids, it’s very innocent.”

Michael’s brother Marlon also refuted the claims made in the doco. 

“I want them to understand and know that this documentary is not telling truth,” he said. “There has not been not one piece of evidence that corroborates their story.”

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