I blame Glenn Miller, he started it all. One minute I was feeling quite sanguine, the next I was ... well, let's say I was feeling rather more reflective.

The Mother and I were coming out of Brighton's Theatre Royal recently when it happened.

We'd been to see the Glenn Miller Orchestra and it suddenly struck me how well I fitted in with the rest of the audience.

Okay, I was still one of the youngest present, and my head was still one of the few covered by gold (courtesy of L'Oreal) rather than silver threads but I certainly didn't look out of place among the senior citizens.

Gone, I realised, were the days when I appeared far too youthful to enjoy Forties big band music, the days when I was someone who looked as if they would have been happier at The Dome watching Stomp - as hundreds of others were doing that evening.

It didn't help that my son had celebrated his 30th birthday that very day or that he had told me how old he felt.

"Think how I must feel then," I said.

"How do you feel?" he asked.

"Very, very old," I replied.

"What rubbish!" said The Mother who refuses to acknowledge her own seniority and is therefore not keen on me acknowledging my own, let alone having a grandson who freely admits he's reached the big 30.

Age, to The Mother, is still largely a state of mind and has little to do with greying locks, arthritic knees and bifocals.

Unfortunately events of the past week or so have thrown her own mortality, and mine, sharply into focus.

First The Mother got a letter from an insurance company telling her that a policy she'd taken out some years ago was due to mature next month.

"That's to cover my funeral expenses, although I'm certainly not making any immediate plans!' she told me. There should be enough left over to put towards your own," she said.

The following day I received a forecast of the retirement pension I'll receive in my old age, a future which is becoming rather too close for comfort.

The realisation that she'll soon have a daughter who has a bus pass in her purse did little to please The Mother.

Then the Queen Mum died. "I can remember hearing the news that George the Sixth was dead," I said as we watched the television coverage of the funeral.

"I can remember the death of George the Fifth," she replied. "And the day war broke out."

"I don't think I like getting old," I told The Mother. "Well, I prefer it to the alternative," she said.

She has a point. And, of course, while you have a parent still alive then you remain a child, if only in their eyes.

Anyway, The Mother continued, "People today can do all sorts of things to avoid looking their age. For instance, you could have plastic surgery when you can't stand the sight of your crow's feet any longer.

"All the stars do it. In fact I've just been reading that Robert Redford has had a facelift."

I was utterly dismayed. "Robert Redford? That can't be true!" I cried.

"He was my favourite heartthrob when I was in my 20s. He was gorgeous, young and blond and muscular, and now ..."

And now he's an old man, said The Mother.

We decided the atmosphere was becoming far too sombre.

Let's have some music, The Mother suggested. I know, why don't we have a spot of Glenn Miller?

Sorry, I said, I'm just not in the mood...