I was fascinated to read about the progressive work Brain Research Trust carries out and knew instantly that, if I couldn't run for them, I wouldn't run at all.  Part of the hardest aspect of my dad's brain tumour diagnosis - aside from the sheer disbelief - was the feeling of utter helplessness. My dad led an extremely active life and worked as a rocket scientist (I still smile when I hear the phrase "It's not rocket science you know!") and I still cannot get my head around the fact that by the time the tumour was found, we were told it was only 4 weeks from killing him. Due to the complexities and delicate nature of working near the brain, nothing whatsoever could be done and my dad died exactly, to the day, 4 weeks later. His time-keeping was always impeccable and even in death, he stuck to his 'deadline'. His passing has shattered my life forever and my dad was my biggest fan of my running so continuing to run, without him being at the finish line, has been painfully hard. But one of my dad's biggest regrets he told me, as he sat at the start line with me one Sunday morning before he died, was that he had never run a marathon when he was well enough to. It means everything to be able to run the London Marathon, knowing that - whilst he won't be standing at the finish line - he will be with me there every step of the way.