"We're just taking things day by day," she said.
"When he gets back home he'll be a while recovering but he's on the mend."
Mrs Scott did not know how long Matthew would be kept in hospital.
The bike event was held on farmer Marshall Jury's property. He said the accident was "just one of those things".
"He's fallen off and the next rider has come over the brow and just happened to clip him."
Mr Jury said he had hosted the Easter weekend event for the past five years and there had been very few accidents in that time.
"It's professionally run and gives the kids from town a chance to let loose," he said.
The children who took part were aged 12 and under, he said, and rode bikes from 50cc to 125cc, depending on their age.
The other boy involved in the accident broke his arm. His mother, Mary Cook, did not want to comment other than to say it was an accident.
The Honda Kids Campout Series is run by Nelson company Power Adventures.
Greg Power, a director and shareholder in the company, said he did not want to talk about the accident and hung up.
A statement released by Power Adventures before the event said riding was on easy-going farm paddocks and farm tracks and the course was short but interesting.
The camp was run in conjunction with Langlands Motorcycles.
Langlands spokeswoman Amber Greenfield said more than 150 adults and children attended the weekend.