E Jane Dickson: Childminder, role model, sage... and the only one who can tell mummy off

Today is Grandparents' Day. But the older generation is vital for all seasons

Break out the Werther's Originals. It's National Grandparents' Day. It's possible this important festival in the crammed Hallmark calendar has slipped your notice, but there's still time to celebrate and there are some great deals out there. Imagine the smile on your parents' apple-cheeked faces when, for example, you suggest they honour the occasion by taking advantage of a leading finance company's "Grandparents' Day" promotion to transfer a chunk of dosh to your children's offshore bank account. As the marketing literature says: "It's the humbug that lasts and lasts." OK, so I made that last bit up, but the "deal" is real. Is it any wonder Britain's grandparents are feeling a mite disgruntled?

Earlier this year the internet support group grannynet.co.uk put out a call for a Grandparents' Charter defining the rights and responsibilities of this powerful social sector. As the site points out, grannies and grandpas are increasingly being hauled back into the family picture by cash-strapped parents in need of financial support and/or childcare.

With City bonuses disappearing like faery gold, the £35,000 a year nanny (to say nothing of the "weekend nanny") is an endangered breed. Further down the salary scale, where margins are tighter and the need for affordable childcare is arguably more urgent, more and more working parents are saying au revoir to the au pair and appealing to their own parents to step up to the school gate. At the last count (before the credit crunched) grandparents shouldered some 64 per cent of childcare nationally. That figure is sure to rise.

Property prices, too, have had a dramatic effect on family living arrangements, with two generations pooling finances for the roof over their head; "granny flats" now come with real, live grannies while grown-up children without the means to fly the nest are bringing up their families in the parental home.

All of which, on the surface, is marvellous for social cohesion. At a time when Britain appears increasingly terrorised by teenagers, research at the Department of Social Policy and and Social Work at Oxford University points to an established link between grandparental involvement and adolescent well-being, while Ed Balls, Minister for Children, Schools and Families, has gone out of his way to stress the importance of grandparents to children and family life.

It is unsurprising, perhaps, that a Government harried on the subject of affordable childcare should be enthusiastic about informal family arrangements which represent a saving of £6bn a year. (And, hey, if our senior citizens are out all day looking after their grandchildren, they won't be needing to spend so much on heating, will they?)

Calls to formalise a carers' package for grandparents have, however, been resolutely ignored. Nor has there been significant advance in legal rights for these "vital" family members. In fractured family situations, Granny and Grandpa are often ideally placed to provide comfort and stability for children in the throes of parental break-up, yet there is no presumption, in case law, of contact rights for grandparents. Contact orders are costly and time consuming to obtain and all but impossible to enforce. It's the same old blinkered story – the official, rosy view of the extended family works only for those already in happy, workable situations; those most urgently in need of family support are left peering in on the happy scene like Dickensian orphans.

It's hardly surprising that that in the time it's taken us to realise their worth, British grandparents have moved on. They're living their own lives, pursuing their own careers (one third of the UK population will become grandparents before the age of 50). We wax lyrical about the Italian model, where, we imagine, steely-haired supergrans rule the family roost (Italy, it might usefully be noted, has the lowest female employment rate in the EU ), but UK grannies these days are as likely to identify with Jane "I'm still worth it" Fonda as with the Dolmio matriarch. They may wish to fit an element of childcare into their busy lives, but we cannot – and should not – count on it.

It's a wonder, frankly, that British grandparents are willing to enter the arena at all, given the collective neurosis of modern parenting; mothers in meltdown when Grandpa slips their sugar-free darling a sweetie, fathers incensed when Granny has the temerity to suggest that not every six-year-old needs one-to-one maths tutoring. The "my house, my rules" shtick works, just about, when you're paying for childcare; when someone is giving their time/money to raise your offspring, it's an arrogance too far. Elderly gift horses have a tendency to bite and it's going to take more than a Grandparents' Day bouquet to bridge this generational divide.

I haven't, as it happens, sent my own parents a card to mark the festival and I'm not confident I can get my children to sing an undoctored version of the world-syndicated Grandparents' Day song ("Granny's special cookies/Boy! They do taste nice...") down the phone.

It's nothing against the day itself which was inaugurated in 1990 by the charity Age Concern to combat marginalisation of the elderly; we just don't, as a family, go in for that kind of thing. We do go in for chatting, though. I speak to my mother and father most days, as do my children. I wish my parents were nearer – we're in London, they're in Ireland – but I doubt we could be closer. I'm fortunate that, despite the distance, we're able to see each other often and if I'm passionate about the involvement of grandparents in family life it's because I know the incalculable advantage this kind of closeness brings.

We forget, in our excitement about cost-saving, that grandparental in-put is not just a matter of man hours (though God knows my own parents have put in plenty), but about an easy, unforced dialogue between generations. When I asked my 12-year-old daughter what she thought the importance of grandparents was, she didn't hesitate: "They're the only people who can over-rule your mum." This, depending on your personal relations, could be a good or bad thing. Personally, I cannot imagine bringing up my children without reference to the higher power of my mother (and it does the kids no harm at all to to raise the bar on table manners/vowel sounds when their grandparents are around).

I've never employed a nanny, largely because it doesn't seem quite good enough to leave small children in the care of someone who may or may not take a bullet for them; grandparents pass this test with flying colours. Also, unless you are an exceptionally irritating kind of parent, there is scant opportunity, in normal social intercourse, for boasting about your children's small daily triumphs. Grandparents lap this stuff up.

Conversely, when you are having trouble convincing your child that, on this or that issue, mother knows best, grandparents can weigh in with a powerful endorsement of your authority.

Cuddles and crisis management aside, a close relationship with a grandparent lengthens a child's perspective on the world and gives them a sense of who they are and where they come from. It was a profound delight to me that the first person to hold my newborn son, after his father and me, was his great-grandmother (two sets of grandparents formed an orderly queue behind). In my slightly bonkers, post-partum state, just the sight of my boy in my grandmother's capable arms brought a crashing physical relief. Gran, born to an age and station when women needed more than brains to get on in the world, went into service on her 14th birthday. She cleaned other people's houses for money, her own for pride and frequently had a go at mine, for love.

When she arrived for visits she kept her hat on until she'd wiped all surfaces to her own (impossible) standards, and household bleach remains, for me, the essential scent of female omnicompetence.

I can't say I inherited the good housekeeping gene, but Gran's other qualities – her "chin up" bravura and mordant wit inspire me still. She died six years ago and not a day goes past that I don't hear her voice – chiding, bracing, always loving – in my head. That voice, that vivid personality, handed down through my mother, now surfaces occasionally in my son and daughter. It's not a spooky thing. It's a deep comfort to me that my London children have in their lexicon jokes first cracked a century ago in rural Lanarkshire. I read this as proof of Philip Larkin's tentative assertion of immortality; "What will survive of us is love."

All honour, then, to this special bond across the generations and not just as a once-a-year obligation. Because Grandparents aren't just for Grandparents' Day. Grandparents are the future.