After the collision, which occurred about 6.35pm, Oceana was taken to Rotorua Hospital where family members were told a broken back was among her injuries.
"We didn't know the full extent of what had happened."
Just before midnight, she was taken to Middlemore Hospital via helicopter then spent three days in the intensive care unit, Newson said.
"My dad and her mum drove up on Wednesday morning first thing and went straight into a meeting with the head of departments in the spinal team.
"They were told as soon as they stepped in she had severed her spinal cord so wouldn't be able to walk unassisted again.
"To go from having full function. To not be able to use her legs is huge. But she's a strong girl and will work hard to maintain her life. But it looks very different for her now than it did a week ago."
A week ago Oceana was "a normal teenager" enjoying the school holidays and hanging out with friends. She was training for the netball team she had been named a part of.
Now the family wonders when she will be able to go back to school.