Police Scotland said that David McPherson, 68; his wife, Elza McPherson; and their unnamed, two-year-old grandson all died in the accident on the A9 in the Highlands on on Tuesday.
Mr McPherson, who was driving a red Ford fiesta, was pronounced dead at the scene.
Mrs McPherson and her grandson were taken to hospital after the accident, which took place at the Slochd Summit near Carrbridge shortly before noon on Tuesday July 5, but died a short time later.
A 67-year-old man and a 65-year-old woman who were in a black Mercedes C Class that was also involved in the crash were injured and were taken to hospital, where they are said to be in a stable condition.
A white Mercedes Sprinter pick-up vehicle was also involved in the collision, with the male driver of that vehicle uninjured.
The road was closed for nine hours while crash scene investigators conducted inquiries into the circumstances of the collision.
Sergeant Neil MacDonald, of the road policing unit, said: "Our thoughts are with the family and friends of the deceased and the family have requested that their privacy is respected at this time.
"We are conducting extensive inquiries into the circumstances of this incident and are appealing for anyone with information to come forward.
"In particular, I would ask anyone with dashcam devices to check their footage as it could hold images which could prove to be significant in our inquiries."