A parliamentary report has concluded that around 400 epilepsy-linked deaths each year are avoidable. Roger Scrivens tells the story of his daughter, Becky, who died aged 11 in 2004.
Becky had her first seizure in the middle of the night, aged nine. By 7.30 the next morning the family was at the local GP's, and by mid-morning at the paediatrics unit at Basingstoke hospital.
There they were told that Becky had suffered a migraine attack.
As long as it didn't happen very often, they were not to worry, and they should simply offer half a paracetamol for the problem.
"We were so relieved that, even if we had our suspicions, we didn't push it," says Mr Scrivens.
And for the two years that followed, the attacks were indeed sporadic.
That all changed in 2004: Becky had a seizure in the first week of January, and another in the first week of February.
Her mother Sandy went straight to the doctor's.
"He was reluctant to refer her to a specialist but Sandy kept pushing it. Eventually he agreed."
It was February, and they were offered an appointment for April.
Come back later
But Becky had another fit in March, again in the first week. Her parents anxiously phoned the hospital and a helpful receptionist said she had a slot that afternoon.
The paediatrician they saw was also convinced Becky was suffering from migraine, says Mr Scrivens, but said he would carry out some tests.
A first examination showed nothing unusual, but then Becky had an MRI scan.
This gave some cause for concern, and for the first time it was suggested that Becky may have epilepsy.
The family was asked to come back on 7 May 2004 to discuss the results.
Becky died three days before the appointment.
"It was a Monday morning - a school morning. I went to wake up the girls. Becky wasn't moving. I opened the blinds. She still didn't move," says Mr Scrivens.
"I whipped the duvet back. She was face down.
"I knew she was dead."
It was the post-mortem examination that stated categorically that Becky had epilepsy.
She had died, it said, of Sudden Unexpected Death in Epilepsy, or SUDEP.
"The thing was, we had long suspected it was epilepsy - even if we had comforted ourselves with the idea that it was migraine," says Mr Scrivens.
"But we had thought that even if she did have epilepsy the worst that could happen was that she had a seizure in a swimming pool. We had never heard of this.
"Now we think - if only we'd pushed it, Becky would have been given the treatment she needed for epilepsy.
"If only we'd kept at it and got that diagnosis."
Mr Scrivens now campaigns to raise awareness of SUDEP, both among the public at large, but also within the medical profession.
"People just aren't aware of it - but it kills more people in this country than Aids, cot death, put together. That's the message I want to get out there - that failure to diagnose really does cost lives."