As the sister of someone with Asperger's, I know what it means to face challenges. Growing up, I didn't understand how devastating anxiety could be; I still regret, and feel guilty for, the many childish arguments we had. If I had not been so cruel, would things be different? Probably not, no. I've learnt to be patient, let go of any disappointment or anger, and, most significantly, how important it is to love.

When people ask me, "How is your brother doing?" I will often respond with a reluctant, "He's fine." An awkward smile spreading across my face as I search for a change in topic. Knowing, deep down, that I should really respond with, "He's happy. He goes outside with my parents every day- not something he did a few years ago. He is the master of Photoshop and can write computer code. He speaks regularly to the same people he did when he was 12 years old- yes, it's online- but who cares? That's the world we live in now. Every day he faces challenges; he is brave. He taught himself the piano, on my old Casio keyboard, and he writes symphonies. What about your sibling?"

For the first time this year, my brother visited me at my home. To some, this must seem like nothing; I was reduced to tears. For someone with a crippling anxiety, just stepping outside could feel like taking part in a marathon. We all measure challenges differently. Ridiculously, outside of organised races, I hate running along the road- the thought of people looking at me from their cars as I run past, red-faced and out of breath, fills me with dread. Before Christmas, I made myself run down the middle of Canterbury High Street on a Saturday. I did it. I hated every second of it but I did it. Now, as training really kicks in, I run for miles each weekend and it doesn't bother me at all.

By running this marathon, I want to show my brother, and anyone who needs a little inspiration, that even though something may seem scary, terrifying and damn near impossible, when you put to your mind to it, everything is achievable. You must always try to be brave, have courage and believe in yourself.