Later, Antill told her mother about the damage but when reporting the matter to police, said that she did not know who was responsible.
Four weeks later, after consuming alcohol, the defendant repeated the act.
This time, however, Antill came clean to her mother and the police.
"In explanation she stated that she was very angry at her mother's ex-partner and had become frustrated at the damage it had caused her family," court documents said.
"Damaging the vehicle was a way to let out her frustration. She knew it was wrong and that was why she phoned police."
Antill said she was too afraid to admit responsibility after the first incident.
Defence counsel Andrew Dawson told the court the defendant was living in supported accommodation and otherwise doing well.
She was remorseful for the outbursts, he said.
Judge John Macdonald said the crimes were relatively minor but quickly added the proviso: "that's not to encourage you to do similar things in future".
He sentenced Antill to six months' supervision and ordered him to pay for the $564 of damage at $5 a week.