Her favourite thing about being a caring caller is "talking to the people" - something she does twice a week, for a couple of hours.
Whangarei St John's oldest caring caller is 102-year-old Ila Johnson, who says the St John services are vital.
"You press a button and they are there [to help]. They are marvellous people," she said.
Ms Johnson starting volunteering as a caring caller a few years ago because she enjoys talking with people.
The caring caller service is anonymous, which means callers and clients only know each others' first names.
Ms Johnson says of her clients: "We talk about anything. My three favourites are racing, rugby and whisky," Ms Johnson says.
She intends to keep on going "as long as St John's wants me".
Whangarei district caring caller manager Faye Grant said the work volunteers such as Ms Millar and Ms Johnson do is invaluable.
"Caring caller is a huge boost to the community," she said. "St John could not work in New Zealand without its volunteers. There is something like 12,000 nationwide."
But Ms Grant acknowledges that St John cannot survive with volunteers alone.
"We cannot survive without donations. Everywhere, funding's being cut from every organisation. The [television] ads are only asking for $3. Imagine if all New Zealanders got on board."
Whangarei people can donate online at stjohn.org.nz or by calling 0800 ST JOHN (0800 785 646), donating to staff or volunteers out collecting or by making a donation at any ASB branch.
To learn more about St John's caring caller programme, phone Faye Grant on 4339889.