A man and his daughter who had a child together were told their incestuous relationship must stop when they appeared for sentencing in the Dunedin District Court.
The 32-year-old man and 18-year-old woman admitted one charge each of incest, with the woman saying she was in love with her father and the pair had been living as husband and wife.
The relationship began when the daughter was 16 and lasted almost two years. Their child, a girl, was born a year ago, the Otago Daily Times (ODT) reported.
Judge Stephen O'Driscoll told the pair: "This must stop. These sorts of relationships do not last and are fraught with difficulties."
Counsel Bernadette Farnham, for the woman, said both offenders had "a mutual background of abuse and neglect".
The newspaper reported that the woman had lived with inappropriate role models and inappropriate actions towards her by male members of her family.
Psychiatric and psychological reports indicated the pair had genetic sexual attraction, which sometimes happened between family members reunited after a long separation.
Judge O'Driscoll said that when the male offender was 13 he and his 30-year-old foster mother had started a sexual relationship. He was 14 when their daughter was born.
Because of his age at the time of the girl's birth, the ODT reported, he had little to do with her until she was about 16.
He made contact in 2010, and after several visits moved into her family's home. A sexual relationship started in August 2010 and continued until May this year.
The woman had a "difficult and chaotic background rife with sexual inappropriateness", the judge said.
He convicted the daughter and sentenced her to 12 months' supervision, with a condition that she undertake counselling or treatment as directed.
The father carried a greater culpability in the relationship, the judge said, sentencing him to 300 hours' community work and 12 months' supervision.
The father must complete a domestic violence programme, take other counselling as directed and not be in the company of his daughter unless another approved adult was present.
Pre-sentence reports said the man's levels of remorse and insight were low and his risk of reoffending was high, Judge O'Driscoll said.
"This relationship was wrong, and I fail to see how you can justify it."
He warned the pair, who have name suppression, they were "highly likely" to be sent to prison if they appeared again on similar charges.
Which memorial design do you like most?Related story: Christchurch earthquake memorial designs unveiled