It was the first time Mrs Duffy had met her great-great-granddaughter, Isabella Scott, after a plan was hatched by her Auckland-based daughter Vicky Beauchamp and granddaughter Leanne Christie.
The last family get-together for the women was 22 years ago in Auckland, shortly after the birth of Mrs Duffy's great-granddaughter Shontelle Stretton - Isabella's mother.
Mrs Duffy, who lives at Ross Home and Hospital, welcomed the visit from the younger generations of her family for the special morning-tea celebration.
"It's quite a surprise. A very big surprise," she said.
University of Otago gerontology specialist Prof John Campbell said the intergenerational meeting of the women was unusual, but one which could become more common.
The life expectancy of humans had increased by about a decade during the past 40 years, with women having a "true biological superiority" over men when it came to living longer.
In the past, mothers had children at a younger age and those babies had lived longer, he said.
Improvements in transport and technology had also enabled far-flung families to come together more easily for such intergenerational visits, he said.
However, advances in life expectancy were being counter-balanced by mothers increasingly waiting longer to start families, Prof Campbell said.
