Police and paramedics were called to a campsite in the Helston area following a report of a collision between a vehicle and a child at around 12.50pm on Wednesday, May 12.
The toddler was tragically pronounced dead at the scene and her devastated family is now being supported by specially-trained officers.
A spokesman for Devon and Cornwall Police said: “The collision involved a car towing a caravan and happened on private land.
“The air ambulance also attended the incident. The coroner has been informed and an investigation by officers from the specialist roads policing team continues.”