"Since seeing this video, we’ve opened an investigation," Sgt. Chantal Mackels said Monday.
"Once the investigation is over with, we'll give it to the Crown prosecutor who will analyze it and decide if he's issuing a criminal offence."
Mackels wouldn't say what charges the parents could face.
Besides the fact that the child is underage, none of the five people in the Honda CRV was wearing a seatbelt.
In the video, the boy sits on the edge of the driver's seat, looking relaxed but alert as he grips the steering wheel and drives the vehicle.
His father sits in the passenger seat with the video camera and gives a running commentary, identifying the boy as Samuel from the North Shore.
Dad cheerfully notes as the speed approaches 40 kilometres an hour that "it's a little fast."
Observing that his son is calmly chewing gum as he drives, the father tells him to "smile for the camera," although the boy's mother, who sits in the back seat with a little girl on her lap, apparently tells the father not to distract the boy.
An older boy sits in the back seat beside the mother.
She says something unintelligible at one point and gestures but smiles for the camera when it is pointed at her.
The boy's father tells Samuel he loves him several times and when he hits 70 km/h, dad starts to laugh and says, "He's rolling, he's rolling."
There was no apparent time stamp to indicate when the video was taken, although bloggers noticed it on Friday and copied it before it was quickly removed from YouTube. It has since reappeared on the popular site and several other sites.
The video is one of dozens posted on the site showing young c...