In June 2024, Jake Danby hit two Aboriginal men with his car on a Darwin street, killing one and injuring the other.
He was handed a 12-month community corrections order, with five months in home detention.
Following public uproar the Northern Territory Director of Public Prosecutions appealed the sentence as "manifestly inadequate".
On Friday, Danby's home detention was increased from five months to two years, as three Court of Criminal Appeal judges upheld the application.
Delivering their decision in Darwin, Chief Justice Michael Grant said Danby would also be required to wear an electronic monitoring device.
But the family of the victim, known as Mr Whitehurst for cultural reasons, have expressed their anger and sadness over the latest punishment.
"I have a lot of questions, but right now, my heart is just broken," Toni Whitehurst said.
"I'm strong but I got upset when I was told the new sentence. It's not fair, he (Danby) is still out there, there is no justice."
It emerged in his earlier court case that the 24-year-old driver had bragged in text messages that the man he killed was an "oxygen thief" and he would not go to jail.
He called it a "two for one combo" and texted it was "pretty funny watching them roll around on the road after going over my bonnet".
Ms Whitehurst said those words continue to hurt the grieving family, as she rubbished the new punishment.
Prosecutors argued on appeal on December 11 that the text messages elevated Danby's crime to the aggravated level.
Prosecutor Pat Williams said a jail term of more than two years was required given the seriousness of the offending and public expectations.
But Defence counsel Jon Tippett said the sentencing judge had taken note of Danby's text messages and while being appalled by them gave them appropriate weight.
Supreme Court Justice Sonia Brownhill had given his client a chance of rehabilitation and counselling and he was abiding by his corrections order amid public condemnation of his actions, the defence said.
"The renunciation in this case has been a tarring and feathering by the community," Mr Tippett said.
Courts shouldn't sentence people on the basis of their stupidity or vile comments, he said.
Mr Whitehurst's nephews often ask whether their uncle is and remember him as a funny, humble and kind man.
"They miss him," Ms Whitehurst said.
Danby was not in court on Friday and Mr Tippett declined to comment on the revised sentence outside court.
NT Attorney-General Marie-Clare Boothby has come under fire over the Danby case, accused of not reporting a conflict of interest after it emerged he was her sister's stepson.
Ms Boothby said she never attempted to hide the fact Danby was an extended family member and at no time was she or her office involved in the criminal matter.
13YARN 13 92 76
Lifeline 13 11 14
19°C