A 7-year-old Australian boy who horrified the world a year ago when he was photographed holding the severed head of a Syrian soldier by the hair has created a quandary for the government, which wants to make scores of Australian fighters in the Middle East someone else's problem by revoking their citizenship.

News on Wednesday that the boy's mother has had enough of the horrors of Syria and wants to bring her five children back home to Sydney has prompted questions about how governments should protect their own citizens and how they draw the line between terrorists and their victims.

Sydney-born convicted terrorist Khaled Sharrouf posted a photo on his Twitter account from Syria of his youngest son with his extended arms straining under the weight of the gruesome trophy.

U.S. Secretary of State John Kerry described the image as "one of the most disturbing, stomach-turning, grotesque photographs ever displayed."

Sharrouf also posted a photograph of his three sons posing with him in matching camouflage fatigues and armed with assault rifles and a pistol with an Islamic State flag as a backdrop.

Fairfax Media newspapers reported Wednesday that the Australian family of Sharrouf's Muslim-convert wife, Tara Nettleton, was trying to help her bring her three young boys and two teenage daughters to Sydney.

Asked about the family, Australian Prime Minister Tony Abbott said if the children had committed a crime, they would be treated by the Australian courts the same way as other juvenile offenders.

"But the point I want to stress is that criminals will be punished whether they're young, whether they're old, whether they're male, whether they're female, whether they're criminals abroad or criminals at home," Abbott told reporters.

"Criminals will be punished and to participate in the kind of barbarism that we have seen so often in the Middle East is just wrong. It's morally wrong and it's a crime under Australian law and it will be punished," he said.

There is no evidence that Sharoouf, who slipped out of Australia in late 2013 using his brother's passport because his own had been canceled, wants to return to Australia, the newspapers reported. Police have confirmed he faces an arrest warrant in Australia on terrorism offenses.

Nettleton later took their children to Syria to reunite with her husband, flying with roundtrip tickets for Malaysia to hide from Sydney airport officials their intended final destination.

Nettleton's father, Peter Nettleton, said he did know the family's location and would not comment on the Fairfax report.

"I still love my daughter and hope she comes home safely," he told reporters outside his Sydney home.

Australia used controversial new counterterrorism laws in December to make even visiting the Islamic State movement's stronghold of al-Raqqa province in Syria a criminal offense punishable by 10 years in prison.

Australia has canceled the passports of scores of suspected extremists, preventing would-be jihadis from leaving the country and stranding foreign fighters overseas.

Australia also plans to pass a law to give the government the power to strip citizenship from dual nationals who are suspected terrorists even if they are not convicted of a crime.

More than 100 Australians are suspected to be fighting with the Islamic State movement and other terrorist groups in Syria and Iraq. The government estimates that up to half of those fighters are dual citizens.

The London-based International Center for the Study of Radicalization and Political Violence estimates that up to 250 Australians have joined Sunni militants fighting in Iraq and Syria. The center estimates only 100 U.S. fighters have arrived from an American population more than 13 times larger.

Immigration Minister Peter Dutton said the government would "take a pragmatic approach in relation to children, particularly infants," in decisions on revoking citizenship.

"There's a commonsense approach here, but if adults have broken the Australian law, if they've involved themselves in killings within Syria or elsewhere, they will face the Australian law," Dutton told Sky News television.

The government won't say what will happen to the Sharrouf children.

Terrorism expert Greg Barton, acting director of the Center for Islam and the Modern World, said the case demonstrated that dealing with foreign fighters is more complex than the government's simplistic message.

"The political rhetoric about the kids is that they're not our responsibility," Barton said. "The reality is that if we have any opportunity of bringing these kids out ... we're going to have to focus on helping the kids."

Barton said that while the Sharrouf children are not to blame for their parents taking them to Syria, there also are Australians as young as 17 who have chosen to go with the help of Islamic State online recruiters. Some will be disillusioned and could be rehabilitated, he said.

"We have a responsibility not to export terror," Barton said.

The Cabinet's rejection this week of a proposal to allow Australians without dual nationality to lose their citizenship if they could apply for citizenship from an immigrant parent's homeland shows there is division among ministers over the Australian approach, Barton said.

George Williams, a University of New South Wales constitutional law professor, said there could be a constitutional court challenge of the proposed change to the citizenship law.

"Australia is much better equipped to actually deal with what are dangerous people than the nations that they'll end up stuck in," Williams said.

Sharrouf was among nine Muslim men accused in 2007 of stockpiling bomb-making materials and plotting terrorist attacks in Sydney and Melbourne, Australia's largest cities.

He pleaded guilty to terrorism offenses in 2009 and served less than four years in prison.