UPDATE, WEDNESDAY, MAY 22: There has been further tragedy following last week's Cressy collision, with a third person dying as a result of the head-on smash.
A Bannockburn woman has died in hospital, following the death of a couple last week.
The 56-year-old Bannockburn woman was airlifted to hospital with life-threatening injuries and died in hospital on Wednesday.
Her passenger, a 25-year-old Bannockburn woman, was also airlifted to hospital with serious injuries.
She remains in a serious but stable condition.
A 9-month-old baby boy, who was in a child restraint in the back seat of the vehicle, was not injured.
Major Collision Investigation Unit detectives are continuing to investigate the incident.
EARLIER, FRIDAY, MAY 17: Victoria's road toll continues to horrify, as it reaches 125 deaths after just five months - the highest in a staggering 14 years.
16 people have now died on the roads around Ballarat this year.
The state's road toll was 83 at this time last year, and the dramatic increase has police worried - the last time it was this high was in 2005, when the road toll reached 149 deaths by May 16.
On Friday afternoon, two people died after a head-on collision on the Hamilton Highway at Cressy.
Police confirmed the two occupants of one car died at the scene. The driver of the other car and her passenger were airlifted to hospital with serious injuries, but their other passenger, a nine-month-old baby in a child restraint, was uninjured.
The cause is still under investigation, and witnesses are urged to phone Crime Stoppers.
Ballarat Highway Patrol Senior Sergeant Stuart Gale said it was a tragic loss.
"Police would be devastated at the loss of another two lives," he said.
"Police can't do this alone, the public needs to take responsibility."
Drivers are urged to take care in all conditions - while it was not a factor in the Cressy incident, now is the time to be aware of black ice around the district.
"It was three degrees on Friday morning and there was certainly a bit of frost around," Senior Sergeant Gale said. "In past years we've seen quite a number of collisions due to black ice, so this is a timely reminder to drive according to conditions, watch their speed and stay abreast of local warnings.
"Last year we also saw drivers not preparing properly, a lot of drivers were fined for careless driving. It's important you take that extra five minutes in the mornings, make sure your windscreen is clear, get new wipers if necessary so you have appropriate vision in the front and sides."