A DORSET mum whose son died from a brain tumour joined campaigners at Downing Street to press for compulsory health education in all schools.

Sacha Langton-Gilks is one of three bereaved mothers calling on the government to ensure all pupils are taught Personal, Social and Health Education (PSHE).

They have written jointly to the Education Secretary Justine Greening and the Prime Minister Theresa May, and travelled to London on Wednesday to deliver their letter.

Sacha’s son David, known as DD, died in August 2012 at the age of 16, five years after he was diagnosed with medulloblastoma - the most common form of cancerous brain tumour in children.

By the time DD’s symptoms were fully investigated and the disease was diagnosed, the tumour was large enough to cause significant complications during his treatment.

Singing teacher Sacha, who is lead champion for The Brain Tumour Charity’s HeadSmart campaign to increase awareness of childhood brain tumour symptoms, believes all children and young people should be offered specialist education on a range of issues concerning their health and well-being, including cancer, their biggest killer.

She backs the Teenage Cancer Trust in its drive to take an hour-long presentation into all schools.

Sacha, from Shaftesbury, said: “When my son DD knew he was going to die from his brain and spinal tumours he decided to raise awareness of the HeadSmart campaign in the media and prevent similar deaths and disabilities with the Teenage Cancer Trust’s school education and awareness programme. My nightmare is that his death was for nothing if action is not taken immediately to stop the fall in PSHE provision."

Sarah Lindsell, chief executive of The Brain Tumour Charity, said: “Sacha’s support for HeadSmart and her tireless campaigning to raise awareness of brain tumour symptoms in young people have already helped us to bring about real change.

“Like Sacha, we are determined to reduce it even further to match the best-performing countries. A vital part of the HeadSmart campaign is to make young people themselves aware of the signs and symptoms of childhood brain tumours. Schools can play a key role in that.”

In their letter to Theresa May, they say Department for Education figures show the time secondary schools spend teaching PSHE lessons has fallen by over 32 per cent in just four years, adding if this trend continued, there would be virtually no such lessons left in schools by 2020.