Kate Livingstone: This growing old isn't all it seems

It appears the former pop star has dementia.

This also explains recent reports about him stumbling about the stage and forgetting his words to those songs he’s been signing for decades.

When I was a teenager you were either a Donny Osmond or a David Cassidy fan.

I used to adore Donny and his band of clean cut brothers, but there was a little bit about me that had a soft spot for Mr Cassidy.

Not quite so squeeky clean, even the thought of his cheeky smile and him tossing his fringe away can make me come over all peculiar – and me a respectable grandmother!

And it was difficult to comprehend that charmer with the news that he was now 66 years old and suffering from dementia.

But then in my head I’m still that teenager who was rushing home from school to watch The Patridge Family on TV on Friday evenings or the Osmonds on the Andy Williams show.

It’s a bit scary to think that these people who once gazed down at us from posters on our bedroom wall are now old enough to receive their pension and bus pass. Although I’m not sure if they have bus passes where dear David lives.

There is something to be said for those stars who sadly died far too young but who never get grey hair or a pot belly.

Perfect examples are James Dean – and for all those who said ‘who?’ ask your granny – or Kurt Cobain, do you know he would have been 50 this week?

Taken in their prime, we never get to see them looking old and grey, and there is something poignant about that.

Others who thankfully are still with us have taken to the hair dye and botox to try to cling on to their youthful looks.

And I’m not going to fall into the trap of naming them in case they sue! But you know who you are.

Growing old is something we all have to deal with, although in my head I’m still 21, a quick glance in the mirror tells a different story.

But I’m going to be clinging on to my youth as long as I can so I suppose that I can’t really blame the stars for doing the same.

Sadly for them their ageing process is more documented than mine – usually across newspapers and the internet leaving me downcast.

So be warned Justin Bieber and One Direction fans, it will happen to you too!