The boy and his mother were both airlifted to hospital with serious injuries after the two-car smash.

The 36-year-old mother was driving a station wagon with her partner and two sons when she crashed into a Ute just before 4pm on Coach Road.

Emergency services found the seven-year-old unconscious. He was taken to the Royal Children’s Hospital with serious head injuries Sunday night.

The mother had a broken femur and other leg injuries and was flown to the Royal Melbourne Hospital.

She had been trapped in the car for more than 45 minutes before she was freed by SES and CFA crews.

The partner, who was in the passenger seat and the nine-year-old boy in the back, both escaped serious injury.

Two 19-year-olds in the Ute were uninjured.

Kyneton Highway Patrol Leading Senior Constable Mark Tepper said it was a “horror crash” that prompted a wake-up call for drivers.

He said the ‘T-bone’ type smash happened when the female driver failed to give way along a 100km/h stretch of road.

“It could have easily been a double fatality,” he said.

Leading Senior Constable Tepper said the Ute attempted to avoid the impact but crashed into the station wagon at full force.

“The driver of the Ute has tried to swerve to avoid her but just didn’t make it,” he said.

“He’s impacted into the car and squished the seat part down to about a foot behind the driver.”

The family in the station wagon were from Newport, Victoria. The two teens in the ute were from Kyneton.

Leading Senior Constable Tepper said the speed limit at the Coach Road intersection should be lowered.

“It’s an awkward intersection. It’s basically a T-intersection.”

“We’ve been to a few crashes there. I think the speed limit could be reduced down to 80 at least.”

“It’s probably a reminder to approach any intersection with the thought that someone may pull out. You just don’t know.”

Police investigations are continuing into the crash.