A public memorial will be held at the crash site tonight at 7pm, with masks and social distancing,
It will be on the residential side of Lake Terrace and all are welcome to bring a candle.
Black said her grandparents "were together all the time".
"They lived for each other, and in this horrible tragic accident, it's so nice and it's a blessing that they went together and that they'll always be together."
Her family has received hundreds of messages of support in the days since Abigail and Arno Vizenti's deaths.
Strangers have passed on memories of the pair.
"The ladies from the op shop where my nana was a volunteer just talk about how they'd just always go out of their way to make sure other people were looked after.
"Another op-shop they said they'd come in and Arno would play the piano - because he loved playing music for people. He'd go in there, and she would take some baking in."
"It just blew me away," Black said.
Police are investigating the crash.
- RNZ
