David Hill says the commission will open a hornets' nest

FORMER ABC chairman David Hill said Australians may not be ready for the scale of the abuse a royal commission is likely to uncover.

FORMER ABC chairman David Hill said Australians may not be ready for the scale of the child abuse a national royal commission is likely to uncover.

Mr Hill, a former pupil of Fairbridge Farm School in regional NSW who later wrote a book describing the institutional abuse suffered by its children, said the commission would "open a hornets' nest".

"I think it's going to be very difficult. I think it's going to be very traumatic," he said.

"They shouldn't, but I think a lot of people will feel great shame that this was happening behind their backs."

Mr Hill said many of those who had suffered abuse within the school, run by the British-based Fairbridge Foundation until 1974, had kept their experiences to themselves, hiding them even from their families.

"However traumatic (a royal commission) may be for a large number of people, I don't think that's an excuse to keep it hidden, to keep it covered up," he said.

"Ultimately, I found that people were liberated by the disclosure, and vindicated. I haven't come across anybody who, having opened up, regretted doing so."

Members of the "Forgotten Australians" _ the estimated 500,000 child migrants, Aborigines and other children placed in care in the last century _ have welcomed Julia's Gillard's announcement.

Then prime minister Kevin Rudd and opposition leader Malcolm Turnbull offered them an apology three years ago this Friday.

Cathy Kezelman of Adults Surviving Child Abuse said a royal commission was "well overdue" but that her group was "very happy" with the announcement.

Still, Dr Kezelman warned experience from the story of the Forgotten Australians showed more than an apology would be needed.

"We really need think to look at the process of this commission, that people are treated with sensitivity because it takes a lot of courage to come and make a statement like this," she said.

"Trauma survivors need to feel accepted and heard and not judged, and far more than that, we need to see reparations and ongoing care and support by people who have experience in supporting trauma survivors."

The apology followed a national report on children in institutional care commissioned by the Senate's Community Affairs Committee in 2003.

Former Democrats senator and child migrant Andrew Murray, a committee member who helped broker the apology after leaving parliament, added his support to the Prime Minister's move.

"I'm surprised and gratified that this has occurred," he said.

An apology followed by redress and reparations, including assistance with dealing with the mental and physical health of victims, was needed, Mr Murray said, while crimes committed by carers needed to be tackled.