Her appeal in the High court at Whangarei was heard on Tuesday and Justice Mathew Downs indicated he would deliver his ruling by the end of the week.
Campbell's lawyer Catherine Cull argued the starting point of five years adopted by Judge Duncan Harvey in the District Court was too high.
She said a starting point of between three-and-a-half and four years was appropriate.
Ms Cull said she took issue with Judge Harvey's conclusion Campbell groomed the boy.
Crown prosecutor Sarah Barnaart said it was certainly open to the judge to find there was grooming because Campbell's intention was to gain the confidence and trust of the boy.