My grandparents had dementia. It was heartbreaking to watch their memories fade, and their understanding of the world crumble. Dementia is a disease that affects so many of our grandparents and older relatives. But it's not just a disease that affects the over 75s.

My dad was still in his 60s when he was told he had Alzheimers. By the time he was diagnosed, he had already given up driving, was getting very confused in situations that were fast moving, struggled to hold full conversations and even on occasion wouldn't recognise my mum - his wife of 30+ years.

Being told a loved one has a terminal illness is something most of us will have to face over the course of our lives. It doesn't make it any easier, though. I can't even begin to describe the range of emotions we as a family have been through these past four years. Even as I sit here trying to type, my throat is closing up and I have to remember to breathe deeply. Some days, it's easy to talk about. On others... not to so much.

Alzheimers is as cruel as it is brutal. It seeps into a person's very being, slowly chiseling away at what makes them, them. There are times when I speak to my dad, and it feels just like it did six or seven years ago. Then there are times where I've had to reassure him that the lady in the house with him is my mum, and that he should stay with her and not go home to see his parents (who both died over a decade ago).

What makes this semi-bearable is knowing that there are charities like the Alzheimer's Society. They provide vital support services for people affected by dementia - services I've used myself to get my mum and dad information and reassurance. They also fund research - the only way we'll truly be able to one day beat this disease so no children, husbands, wives or siblings will have to see a loved one go through what my dad is going through.

Me and Jeni want to do our bit - to give back to a charity that's helped me, to give forward to brighten the future, and to give everyone a bloody good laugh as we attempt to trek 26 miles across Wales' mountains (we've already packed snacks).

I know times are tough for us all, but if you have quid or two to spare, please consider donating to our page. It will mean the world, and also give us the much-needed motivation when we're facing down gale force winds or just getting soggy in damp mist.

Thank you xxx

- Katharine and Jeni