Judge Geoffrey Chettle said Kemp's injuries from the crash, including still needing crutches to walk, would make time in jail "unbearable".

"In an understandable way, you want to be punished," he said. 

"Rarely and exceptionally a court will be justified in not imposing such a sentence. In my view, yours is one of those rare and exceptional cases."

Judge Chettle went on to explain although the crash had tragic consequences, jail time did not appropriately reflect her culpability.

"The consequences of your failing to stop are catastrophic. Two young lives have been needlessly lost but nothing this court can do can change that," he said.

"The tragic consequences of your actions cannot dictate the punishment. Justice is not vindictive.

"Nothing this court can do to you will punish you as much as you punish yourself."

However, prosecutor Phillip Teo said Kemp should be jailed as her moral culpability was heightened due to ignoring the legal requirement of putting Savannah into her booster seat.

Kemp had picked Savannah up from kindergarten without telling her sister Bryana and was driving her to Dookie for the afternoon on the day of the crash.

But the youngster was not wearing a full seatbelt or sitting in a booster, with only a lap sash belt protecting her as she sat in the back passenger seat. 

Kemp drove through a stop sign and collided with two other vehicles, hitting the brake three-and-a-half seconds before driving through the intersection of Old Dookie and Boundary roads.

Savannah suffered chest, leg and neck injuries severe enough to kill her at the scene.

Ms Aldridge's son Remi was stillborn at 34 weeks after the collision.

Kemp was sentenced to a two-year community corrections order and will have to perform 250 hours of unpaid community work along with completing programs including a road trauma course.