"It was then I noticed Charlotte was walking with a limp. I asked her if she had been hit by a car and she said a lady had backed into her. She was too afraid to tell because she thought she would get in trouble after the woman growled [at] her," Mrs Morgan said.
"And it's not the first time it's happened."
Mrs Morgan said a young driver had reversed into her daughter as she rode her trike about a year ago, although she had then escaped injury.
The latest collision has left Charlotte with a badly strained ankle and robbed her of the confidence to get back on her trike.
She was wearing a moon boot and using crutches, Mrs Morgan said, and was unable to volunteer at the Montessori School until her sprained ankle had mended.
Mrs Morgan was running her daughter to youth centre dates and had taken her to visit the school "to keep the momentum going for her there".
"But she's not keen to get back on her trike, which is a really big one for us. That trike is her independence. She can't walk very far but she can pedal like the clappers and we're just hoping like mad she will get her nerve back again," she said.
"The police were told but there's no point looking for the driver. Apparently, Charlotte's not the first on an adult trike to be knocked over in Masterton in the past few weeks. People have to take more notice and take care, be aware, whenever they're behind the wheel."