Srs Madeleine (80) and Adrienne (82), who live in Oamaru, will be joined by Srs Catherine (Mosgiel) and Genevieve (Auckland) to celebrate 60 years since they made their profession (commitment for life).
The four entered the convent together in 1948.
At least 20 Dominican Sisters are expected to attend a function being held to mark the occasion, with the Catholic Women's League organising a meal and the St Vincent de Paul Society providing a cake.
The Dominican family was close-knit and, when sisters got together, there was a lot of laughing involved, Sr Madeleine said yesterday.
Sr Madeleine, who grew up at Warrington, got to know the Dominican Sisters while attending St Dominics in Dunedin.
Two of her sisters were also Dominican Sisters and she had a brother who was a priest, so entering the convent was "always on the cards".
Her parents were very supportive of her decision and, in those days, it was not so uncommon, she said.
Asked why she chose to enter the convent, Sr Madeleine said: "I'd been given life, so I needed to use it properly".
Sr Adrienne, who grew up in the North Island, had wanted to be a nun since she was a young girl.
She remembered two Dominican Sisters coming to school one day and she thought they were "so wonderful", she wanted to join them.
Sr Madeleine has lived in North Otago for 20 years - "I wouldn't live anywhere else" - while Sr Adrienne is in her 10th year in Oamaru.
Sr Madeleine, who taught at schools in Auckland, Invercargill, Dunedin and Oamaru, has maintained a close association with St Kevins College.
She taught at the school and, after leaving, spent 11 years on the school's board.
She had retained friendships with many of her pupils, describing them as friends, not ex-pupils.
