Rata Hill, grandmother of 15-year-old Niko Hill who died in the crash, said she read about the accident on social media before she knew who had died.
She felt heartbroken for the families affected, and couldn't sleep as she worried for them.
"I stood in the tears of rain and said 'I'm so sorry you boys died, stay together and comfort one another'.
"Just after 2.30am I thought families would be finding out their loved one had passed. I thought to myself 'it's okay, my phone hasn't rung'."
She said the sadness she had endured since losing Niko had been unbearable.
"Our lives have changed, I have an emptiness."
Police initially charged Fleming with five counts of manslaughter, but he pleaded guilty to the lesser charges of dangerous driving causing death in April.
The judge also disqualified him from driving for five years.
Justice Rob Osborne told the packed courtroom the Crown's starting point of five or six years in prison had been reduced to recognise Fleming's young age and circumstances.
He said the regret displayed by Fleming in restorative justice conferences also contributed to the reduced sentencing.
Stephen Drummond, father of crash victim Javarney Drummond, said two-and-a-half years in prison meant nothing.
"I don't think a lot of it to be honest with you, he killed five kids.
"You choose to drink, and you drive and everything else, it wasn't just pure accident."
But lawyer Steve Cullen, who deals regularly with cases involving drink-driving, said it was a relatively normal sentence given the circumstances.
"It's certainly within the parameters of normal sentencing for this type of offending. The judge has to look at ... the fact that he's dealing with a very young person who's simply being sentenced for an act of carelessness, not deliberate wrongdoing.
"The vast majority of the populous don't come before the court for charges of this nature, so the people who come before the court tend to be vulnerable, hurting people who've had difficult circumstances in their lifestyle, so the court has to recognise that."
Students Against Dangerous Driving general manager Donna Govorko agreed that no sentencing would ever recognise the pain caused to the families.
"The decisions that were made that day obviously had tragic consequences, and unfortunately these decisions are being made by young men and women daily," she said.
She said more education was needed for young people to understand the seriousness of illegal and impaired driving.
"This is a culture that needs to change within this country, you know we need to start asking ourselves some really serious questions about what do we want as a country to happen."
Fleming told the victims' families through his lawyer that he was truly sorry, angry and ashamed of his decisions.
