A four year old boy is being treated at Frenchay Hospital near Bristol for serious head injuries after a crash on the A3072 near Holsworthy.
He and a 32 year old woman were in a car, which overturned on the road. She sustained back injuries.
Police would like to hear from anyone who saw the accident, which happened between Weekstone Cross and Weekstone Cottage just after 1pm on Saturday afternoon.
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An overcast start with cloud spreading from the east to Devon and Cornwall. Cool winds and isolated showers in parts of South Devon
An overcast start with plenty of cloud filling in from the east. Some isolated showers in Somerset and Dorset. Highs of 8 or 9 degrees.