The family of a four-year-old boy filmed on top of a car as it drove down a West Australian highway has denied knowing their child was on the roof.
The parents of a child filmed riding on the roof of a car as it sped along a busy West Australian highway say they have been "traumatised" by the experience.
Footage of the four and a half-year-old posted to social media on Friday shows the boy clinging to the roof rack of a Holden SUV as it was driven through Perth's southern suburbs.
At one point the vehicle enters Tonkin Highway, which has a speed limit of 100km/h.
Speaking through a representative on Tuesday, his family said they were "shell shocked" by the incident.
National Indigenous Critical Response Services national co-ordinator Gerry Georgatos said the public backlash had "traumatised" the child's parents and siblings.
"It was an extraordinary, freakish occurrence," Mr Georgatos told AAP on Tuesday.
The family claims the boy must have climbed on top of the vehicle by himself.
"Kids love to climb things, they'll get up trees, climb benchtops," Mr Georgatos said.
He denied the mother knew her son was on the roof, adding it wasn't until frantic motorists managed to flag her down the woman realised something was wrong.
Police say the car stopped and the boy was placed back inside before the driver was pulled over at a Harrisdale petrol station.
Officers say three children were seen in the car, including a four-year-old boy not wearing restraints.
A 36-year-old mother of six is facing dangerous driving charges and will be summonsed to appear in court at a later date.
But the family say their trauma has been compounded by online trolling.
Mr Georgatos said people on social media had been making "wild accusations" and "near-libellous" claims.
"These are salt of the earth, good people," he said. "They're just thankful their child is alive and well."
The NICRS will be providing ongoing counselling for the family.