Parents critical after major crash on Calder Freeway that killed toddler

A Melbourne mum and dad are fighting for life following a major crash on the Calder Freeway that killed their two-year-old daughter and left their baby also critically injured.

The collision occurred about 2.30pm yesterday when a semi-trailer carrying grain struck three cars, including one towing a boat, at Diggers Rest near the Bulla Road overpass.

The two-year-old child, who was in the backseat of one of the cars, died almost instantly.

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Her one-year-old sister was taken to the Royal Children's Hospital in a critical condition.

Fortunately, the baby's condition has now been downgraded to stable.

However, the girls' parents, a 35-year-old Caulfield South man and a 37-year-old Caulfield South woman, are still in a critical condition in hospital.

Another driver, a 62-year-old man from South Melbourne, who ended up trapped under the truck was also taken to hospital in a critical condition.

He is now in a stable condition at the Royal Melbourne Hospital.

The 42-year-old truck driver from Donald was taken into police custody after the crash and interviewed for five hours before being released.

Detective Sergeant Mark Amos spoke of his horror following the incident yesterday afternoon.

"This is just a catastrophe. It's an absolute disaster," he said.

Two people who were in another vehicle were not seriously injured.

Firefighters worked to free the victims from the cars, with one man having been trapped in his car under the overturned truck.

The freeway was blocked inbound for the rest of Monday.

Police are keen to speak to any witnesses or anyone with dashcam footage that may have been in the area at the time of the collision.

Anyone with information is urged to contact Crime Stoppers on 1800 333 000 or submit a report online at www.crimestoppersvic.com.au.