A Sudanese refugee mother who claimed witchcraft made her drive into a lake in Melbourne killing her three youngest children has been jailed for 26 years.

Akon Guode, 37, was sentenced to a maximum of 26 years and six months with a non-parole period of 20 years over the deaths of her three children and attempted murder of a fourth child on Tuesday.

The Sudanese refugee wailed in court as Justice Lex Lasry outlined the difficult personal circumstances Guode had experienced in the years before she killed her one-year-old son Bol, and four-year-old twins Hanger and Madi, by driving her 4WD into a Wyndham Vale lake on April 8, 2015.

'People don't understand why you did what you did,' the Victorian Supreme Court judge said.

'In my opinion your actions were the product of extreme desperation.'

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Akon Guode (left) has been jailed for 26 years for murdering three of her children and trying to kill a fourth

One-year-old Bol and four-year-old twins Hanger and Maudit all died when their mother intentionally drove a car carrying them into a Melbourne lake

Joseph Tito Manyang (pictuered right) leaves the Melbourne Supreme Court after Guode was sentenced to 26 years prison for killing three of their children

Guode had an affair with Manyang (right) after moving in with him and his wife

The African migrant claimed witchcraft made her drive into a lake in Melbourne, killing her three kids. She is pictured at their funeral in 2015

Justice Lasry said Guode had suffered post-traumatic stress disorder after moving from Sudan to Australia.

'You watched your husband be shot to death before being repeatedly raped until you were unconscious,' he said.

'In some respect, this sentence is inadequate but at the same time excessive for what you have been through'.

He said she had committed a 'horrendous crime on innocent children' which was a 'total betrayal of trust'.

Guode came to Australia with three children in 2006 from Sudan after her soldier husband was killed in civil war.

After moving to Victoria she lived with her dead husband's cousin, Joseph Manyang and his wife, began an affair with Mr Manyang and bore him four children.

Her relationship with Mr Manyang caused her to become isolated from the Sudanese community, which was gossiping about the affair.

She was also depressed and in debt at the time she drove into the lake.

Justice Lasry said Guode had suffered post-traumatic stress disorder after moving from Sudan to Australia

A 4WD is removed from Lake Gladman, Melbourne on April 9, 2015 after Guode drove it into the lake

Police established Guode had to make at least three turns before the car carrying her four youngest children entered Lake Gladman.

After the bodies of her children were pulled from the lake, Guode was interviewed by police but released without charge.

In July 2016, police released a statement that alleged Guode had spoken about killing herself and her children the day of the murders, the ABC reported.

It was also reported that a court had heard she owed large debts.

The court was told Guode had sent almost $100,000 to family in South Sudan from when she moved to Australia in 2008, according to the ABC.

The mother-of-seven blamed a dizzy spell for causing her to lose control of the car

Earlier in June of 2016, a court heard a 000 call from the moment Guode drove into the lake.

A witness could be heard in a recording saying: 'I saw them just drive full bolt into the water'.

After the bodies of her children were pulled from the lake, the mother-of-seven blamed a dizzy spell for causing her to lose control of the car.

But an investigator said the car was deliberately driven into the water.

Several police re-enactments showed the car could not have drifted off the roadway, as Guode claimed.

The re-enactments also demonstrated a driver would need to turn the steering wheel three times to get into the water.

A coffin with the bodies of one of the three children during a funeral service on April 18, 2015

Several passers-by and witnesses recalled hearing the car's engine's revving after it had landed in the water.

A key witness also testified that Guode believed witchcraft had caused the crash.

Guode had told the woman she thought she was under a 'spell' when she drove into Lake Gladman.

The woman said Guode believed her lover's wife may have used a witch doctor against her.

The witness gave evidence she overheard Guode say she would 'rather take her own life and that of the kids' than see them live with her lover, Joseph Manyang, and his wife.

During Guode's committal hearing Mr Manyang said he believed it was an accident and continued to visit Guode in prison.

He said she was a good mother who loved all her children.

Guode will return to court on January 31.

WHO IS AKON GUODE? * She comes to Australia as refugee in 2006 with her three oldest children to escape war-torn Sudan where her first husband died. * She stays with her dead husband's cousin, Joseph Manyang and his wife and children. * Guode and Manyang start an affair in 2008 and have a daughter, Alual in 2009. * Guode gives birth to twins Hanger and her brother Madit in 2010, Manyang leaves his wife. * Guode also has another son, Bol, with Manyang. HOW HER CHILDREN DIED: * On April 8, 2015, the mother-of-seven drives her 4WD into a Melbourne lake, with four of her children inside. * Her one-year-old son, Bol, and the four-year-old twins die. * Six-year-old daughter Alual is hospitalised but survives. ARREST: * Guode is questioned by police and released without charge. * She tells family members she felt dizzy before the crash. * Community rallies behind her and her family to help pay for funerals. * Guode is interviewed again in August, charged with three counts of murder, one count of attempted murder and taken into custody. POLICE CASE: * Police say CCTV footage shows Guode drive past Lake Gladman five times before her car plunges into the water. * They allege Guode's car appears to make three distinct steering moves before entering the water without braking. * Prosecutors allege she drove 'full bolt' into lake. * Court hears that at the time, Guode was being chased by debt collectors. * On the day of the murders, a rumour circulated that due to community pressure, the children's father, Joseph Manyang, was leaving the Guode home and moving back with his wife. COMMITTAL: * Guode breaks down during several emotional court hearings and begs for bail. * Joseph Manyang says he does not believe she could harm their children. * Court hears she suffered depression-like symptoms in the years before the deaths and struggled to cope with a community backlash over her affair with Mr Manyang. * Key witness who allegedly heard Guode admit to causing the deaths fails to appear to give evidence, telling a police officer she'd be 'gotten rid of' if she testified. * Court hears Guode believe witchcraft caused the crash and that she was under a 'spell' when she drove into the lake. HEADING FOR TRIAL: * Guode enters a plea of not guilty in August to the charges and is committed for trial, to take place in late January. * Avoids trial with guilty pleas on Monday to the infanticide of Bol, the murders of Hanger and Madit, and attempted murder of Alual.