New research has shown that up to five children a day suffer strokes that go undiagnosed due to a lack of awareness of the condition.
Scientists at Bristol University are to launch a study of six million youngsters in a bid to combat the "striking lack of public and medical awareness" of childhood stroke, which is thought to be as prevalent as some cancers.
The researchers will monitor victims for a year after their first attack to find out more about the symptoms - and their consequences if left untreated.
In children the average time between the onset of symptoms to presentation to a medical professional is five-and-a-half hours, meaning many young stroke sufferers are diagnosed too late to benefit from life-saving treatments.
Paediatric neurologists, physiotherapists and radiologists are all collaborating on the Study of Childhood Stroke, which will run for 12 months.
Dr Finbar O'Callaghan, senior clinical lecturer in the Division of Child Health, said: "Stroke in children is not as rare as many people may believe. The incidence is not fully known, but at least one child per day has a stroke in the UK and it may be as high as five per day."