A baby has died following the head-on crash on the Pacific Highway at Emerald Beach on Friday.
The 10-month-old boy admitted to Coffs Harbour Base Hospital with serious head injuries died in hospital on Saturday about 7.30pm.
The accident happened 50 metres south of the Smiths Rd intersection around 3.30pm.
Police crash scene investigators have found a silver Ford Falcon headed south crossed onto the wrong side of the road and collided with a north-bound black Holden Statesman.
Police said the 30-year-old male driver of the Falcon was conveyed to hospital along with his wife, 26, daughter, 3, and 10-month-old son.
The baby was admitted with serious head injuries whilst the toddler suffered only minor injuries.
The driver is being treated for an injury to his kidney and his wife suffered a fractured thumb, police said.
An elderly couple in the other vehicle are said to be in a stable condition after they initially suffered serious injuries.
Police said investigations continue into the tragic accident and a report will be prepared for the Coroner.
Anyone who witnessed the accident near Emerald Beach on Friday afternoon should call Coffs Harbour Police via Crimestoppers on 1800 333 000.