A woman and an 11-month-old baby boy have died in a head-on crash.
About 5pm on Wednesday, a Holden Commodore - being driven by a 40-year-old man - was travelling east on the Golden Highway at Dunedoo.
At the same time, a Hyundai i30, being driven by a 25-year-old woman, was travelling west.
There was four passengers - two men, aged 23 and 29, a 2-year-old girl and an 11-month-old baby boy - in the i30.
The two cars collided head-on killing the 25-year-old woman and the 11-month-old baby.
The 23-year-old male passenger was taken to Dubbo Base Hospital with non-life-threatening injuries, while the 29-year-old man was flown to Westmead Hospital - his injuries are not known.
The girl was airlifted to the Children's Hospital at Westmead where she remains in a serious condition.
The driver of the Holden was also airlifted to Westmead Hospital - his injuries are not considered life-threatening.
The circumstances of the crash are being investigated by officers from the Crash Investigation Unit.