The woman found killed at her home in suburban Auckland was a treasured grandmother who leaves behind a devastated twin, her family says.
A family member said Maria Brown "helped so many people" and had funded the education of many children.
The 77-year-old was found dead at her home in Onehunga's Moana Ave on Sunday morning after phone calls from a family member went unanswered.
There has been limited word from police on the circumstances of her death and no news of any arrests, but police say there is no threat to public safety.
"After the post-mortem examination, police can now confirm the death is being treated as a homicide investigation," Detective Inspector Scott Beard said.
"A police presence remains at the address however we would like to reassure the community this is believed to be an isolated incident and we are following good lines of inquiry."
Police had initially said Brown was aged 65, but today corrected this to 77.
Her adopted granddaughter, Fetu Leiloanaisaua Leapai-Saili, spoke to the Herald from her home in Apia, Samoa, to pay tribute to Brown.
Leapai-Saili said her nana, a widow who lived alone, left a twin sister, who lives in American Samoa.
Born and raised on Savai'i, Brown had emigrated to New Zealand with family many years ago.
Leapai-Saili said Brown and her twin had adopted and raised her mother.
"They basically raised my mum and us," she said.
"I'm grateful that she took my mum under her wing and raised her and raised us as well.
"Because we wouldn't be where we are right now without her help."
Her nana would always go the extra mile for her family and for anyone and everyone in need, Leapai-Saili.
"She loved so many people. She helped put so many kids in school.
"Paid for school fees, every time she comes here she makes sure everyone gets lunch money.
"Everyone gets a share."
Brown had five children and many grandchildren, Leapai-Saili said.
Leapai-Saili said the family were waiting for police to confirm her cause of death.
"She has been living there for more than 10 years and her neighbours are so lovely as well."
Leapai-Saili said she remembered Brown counselling her about life, especially marriage.
"So, now I'm married with a son, and I can think of all she has taught me, I can definitely say 'you did a great job Grandma, thank you'.
"Now my marriage seems balanced and good, because you have taught me what to be aware of.
"She also was a lovely wife to her husband."
Leapai-Saili said she had comforted Brown's twin, who was devastated by the news of her death.
"Both of them, they loved me so, so, so much."
Brown was due to celebrate her birthday on the day her body was found.
"That's very heartbreaking.
"If police confirm she died on Sunday, then that means she died on her birthday."
Anyone with information is urged to contact police on 105 or anonymously by calling Crime Stoppers on 0800 555 111.