The woman, a 34-year-old Tongan national, had confessed to the smack immediately after one of her two children dobbed her in to Child Youth and Family (CYF) in November last year.
CYF were speaking to the family on an unrelated matter when the seven-year-old boy revealed he got smacked on the hand with a large spoon if he broke rules at home.
His mother was subsequently convicted of child assault.
During the investigation it was found she and her husband had been living in New Zealand illegally since 2009. He was deported in November 2015.
