A father from Wiltshire is taking on the incredible challenge of completing six marathons around the world in memory of his teenage son.

Frank James Lee, from Royal Wootton Bassett, was just 13 years old when he was first diagnosed with glioblastoma.

The teenager had been told to get his eyes checked after complaining of persistent headaches and nausea, but it wasn't until he collapsed at home in 2017 that doctors discovered his high-grade tumour.

Frank died just two years later, on July 22, 2019.

“As a family, we knew nothing about this disease until it completely upended our lives," said the teen's dad, Frank Lee Senior.

“I find it so hard to talk about Little Frank, and a couple of years ago I’m not sure I would have been able to do it.

Frank James Lee and his dad Frank Lee SeniorFrank James Lee and his dad Frank Lee Senior (Image: Brain Tumour Research)

"But I know I need to in order to prevent more parents from losing their sons like we did.

"So many young people die of brain tumours, yet so little funding goes into research into the disease - it makes my blood boil."

Fuelled by his grief and a desperate desire to save the lives of other children, Frank Senior has now set out on a mission to raise thousands for Brain Tumour Research by running not one but six marathons.

The 44-year-old is currently halfway through the gruelling challenge, known as the Abbott World Marathon Majors, and says the training has become his main way of coping.

His team has currently raised more than £27,000 and still has three more marathons in sight - Berlin in September, Chicago in October and finishing with New York in November.

A love for your child can literally send you running around the world for themThe love for your child will literally send you running around the world for them (Image: Brain Tumour Research)

“Any time my mind starts going off and the sadness gets to me, I put on my trainers, and it clears my head,” said the grieving father.

“I couldn’t have made it so far without all the lads who have joined me in running around the world and remembering Little Frank.

"He was such an energetic and sporty kid when he was alive."

Despite the fact that hundreds of young people suffer from brain cancer each year, only one per cent of the national spend on cancer research has been allocated to brain tumours since records began in 2002.

Brain Tumour Research funds research to improve survival rates and patient outcomes in line with other cancers such as breast cancer and leukaemia.

The research charity also campaigns for the Government to invest more in research into brain tumours.