Police have charged the driver of the truck involved in yesterday's crash.
"He has been charged with two counts of dangerous driving cause death and has been remanded to appear in the Ballarat Magistrates' Court later today," police said in a statement.
The truck driver, 59 from Western Australia, was not hurt in the crash.
It has been confirmed those killed in the crash were a woman, 37, and a boy, 5, both from Epsom.
Police said a nine-year-old boy injured in the crash is in hospital in a critical but stable condition.
A 37-year-old man suffered minor injuries.
A Bendigo mother and son have died in a crash near Creswick which also left a nine-year-old boy and his father injured.
Police are investigating the circumstances surrounding the double fatality on the Allendale-Kingston Road, to the north of Kingston, on Sunday afternoon.
Officers say a Kenworth Prime Mover was heading west along Church Parade when it failed to give way and hit a white Rav 4 travelling south at about 12.20pm.
The family of four and their pet dog were in the car at the time.
A 37-year-old woman and five-year-old child in the car died at the scene.
A nine-year-old boy was rushed by air ambulance to the Royal Children's Hospital facial injuries. He is in a stable condition.
The 37-year-old male driver was taken by road ambulance to Ballarat Hospital with minor injuries and was treated for shock. He remains in a stable condition.
The 59-year-old truck driver from Western Australia was taken to hospital to have blood taken. He is assisting police with their inquiries.
Detective Sergeant Paul Lineham, who is heading the Major Collision Investigation Unit dealing with the crash scene, said the collision had caused "needless" loss of life.
The deaths bring the number of lives lost on Victorian roads in 2019 to 261. This is 50 more than at the same time last year. More than half of the road deaths in 2019 have taken place on rural Victorian roads.
Officers at the scene urged drivers to take due care and attention, and take a break if travelling a long distance.
A major crash has taken place on the Allendale-Kingston road in Kingston claiming two lives.
Police are investigating the circumstances surrounding the double fatality at the Church Parade intersection just to the north of the town Kingston, near Creswick, this afternoon.
One young child and woman from the car died at the scene and another, a 10 year old, has been rushed by air ambulance to Melbourne.
An Ambulance Victoria spokesperson said the child had suffered facial injuries and was now in a stable condition.
The male driver of the 4WD has been taken by road ambulance to hospital with minor injuries and was treated for shock. He remains in a stable condition.
The driver of the truck that is believed to have been travelling west along Church Parade was uninjured and is currently assisting police with their enquiries.
The white 4WD came to rest on the south side of the main Kingston thoroughfare where emergency workers cordoned it off.
Two vehicles were reportedly involved in the accident: a four-wheel drive and a Kenworth truck. The circumstances of the accident have not yet been established.
The Victorian road toll at this stage for 2019 is 263 compared to 211 in 2018.
Emergency services were first notified at 12.19 on Sunday afternoon to reports of a car rollover at the location about 26 kilometres north of Ballarat.
An ambulance spokesperson said an air ambulance was on the scene and would be transporting a little boy for further treatment in Melbourne. The air ambulance has since left the scene.
A man in his thirties is being taken to Ballarat Base Hospital, and a number of people are still being treated at the scene.
Two people are believed to be still trapped in one of the vehicles.
The extent of the injuries of those involved are not yet known.
A police spokesperson said that major collision investigation detectives were heading to the scene.
The road is currently closed in both directions.
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