A girl of eight watched in horror as her older sister was knocked down and killed by a truck, seconds after they stepped off a school bus.

Brittany Davis, 10, described as having a "beautiful singing voice", did not see the truck approaching and was run over in front of her schoolfriends and her sister Taylor on the winding country road near Clevedon, south of Auckland, on Friday.

Her father, Howard Davis, used his bare hands to try to dig his daughter out from under the wheels of the truck as he shouted for help.

Last night, Brittany's mother, Delwyn Davis, broke down in tears as she spoke of her "wonderful" girl.

"She was just a fantastic child, one in a million. She was a little angel, and now she is a little angel."

Mrs Davis said the family was still in a state of shock, and last night they had gathered at home as Brittany's body was brought home to rest.

"We've been waiting for her to come home since yesterday. We've just got to get her home. We're still dealing with our grief. I'd love to sit down and talk about how wonderful she is but we've just got to get her home first," said Mrs Davis as she choked back sobs.

"She's going to come home for a few days and then we'll decide what to do. No one knows what to say. We don't know what to say either."

Neighbours were visibly upset as they told of how Brittany's distraught father frantically scraped at the ground to free his child, while the shocked driver also came to her aid and was seen feeling for her pulse.

Sister Taylor escaped injury because she hesitated before stepping out.

Police are investigating the crash, the latest in a string involving children hurt or killed after riding school buses.

Neighbour Alison Dawson, whose grandchildren went to Clevedon School with the sisters, said Brittany was a pretty, bubbly, friendly girl who often rode the school bus. She said Brittany's parents were being comforted by their extended family. Howard is understood to be a nephew of the Maori Queen, Dame Te Atairangikaahu. The family had moved to the area within the past two years and were valued members of the community, Mrs Dawson said.

Clevedon School board of trustees chairman Martin Grant, who has a son in Brittany's class, said she was known for her beautiful singing voice and would be missed.

"It's one of those awful twists of fate," he said. "We feel, as parents, for what that family must be going through."

A Ministry of Education trauma team would be at the school on Monday.

He did not know of any similar incidents involving the school bus in the 12 years he had lived in the area.

Kawakawa Bay Fire Brigade officer Bill Couldrey said the road between Clevedon and Kawakawa Bay was "windy and dangerous" but police were still investigating the crash's contributing factors.

The driver of the truck was a Works Infrastructure employee who was working on a Manukau City Council project in Kawakawa Bay.

A colleague said the man was "well liked, a good person all round" and witnesses said he helped at the crash scene.

Works Infrastructure chief executive Paul Reedy said last night an investigation was under way. He said the driver was undergoing counselling.

"This time is one of considerable sadness for all. We at Works Infrastructure are very distressed about this tragic accident and wish to extend our thoughts and support to all of those involved."

-Additional reporting Amanda Spratt