Two refugees from South Sudan who rorted almost $1 million from the Commonwealth in a childcare scam have been jailed, with a judge saying the publicity would add to the "trauma" of a community already subject to "unjustified vilification".

Key points: Rosa Riak and her son Kuol Deng have been jailed for four years after scamming the Commonwealth of almost $1 million

Rosa Riak and her son Kuol Deng have been jailed for four years after scamming the Commonwealth of almost $1 million The family's company employed dozens of people who pretended to care for children in their homes so they could claim a government benefit

The family's company employed dozens of people who pretended to care for children in their homes so they could claim a government benefit They can apply for parole after two years

Rosa Riak, who became an Australian citizen in 2006, pleaded guilty to one count of dishonestly causing a loss to the Department of Education and Training.

She was charged as part of an investigation into close to $16 million in false payments to day care providers in Melbourne's west.

The County Court jailed Riak and her son Kuol Deng for four years, while her daughter Achai Deng left court with a good behaviour bond.

Judge Michael McInerney said their fraudulent actions exposed fatal flaws and clear gaps in the Commonwealth childcare system.

"The prisoners here have certainly utilised such gaps to the full by their flagrant and sustained attack on the revenue of this country," Judge McInerney said.

The family's company, called The Deng Group, employed dozens of people who pretended to care for children in their own homes.

Kuol Deng was caught on camera asking his mother where he should put $80,000 in cash. ( ABC News, file photo )

The court heard the family's fraudulent scheme targeted the Commonwealth's Grandparent Child Care Benefit, which could pay $1,750 a week per child.

At least $955,438 was paid out in fake claims and the family's company received up to $159,300.

But Judge McInerney stressed that those figures were only the minimum amounts that could be proven.

Deng, who owned a $165,000 Range Rover, was undone by surveillance which showed him asking his mother where he should put $80,000 in cash.

Judge McInerney said Riak and her children were ashamed and sorry for their actions.

He said publicity of the case would further harm the local African-Australian community, which has been struggling with the issue of youth crime.

African-Australian community leaders in Melbourne say they have been subject to unfair media attention on "African gangs", when the majority of the community is law-abiding.

"Your community has been subject to much unjustified vilification in recent times," Judge McInerney said.

"By your actions and the publicity that no doubt this sentence will get, you have added to that trauma your community must endure."

Riak and Deng can apply for parole after two years.