My son's granny has taught him how to use e-mail. “It's so that she and I can stay in touch,” he explains with a four-year-old's seriousness: “We have important things to discuss.” As well as imparting pearls of computer wizardry and wisdom, Granny B is also teaching Joe to play chess, and let's not forget sixtysomething Nanny Choo, who gamely plays football with him and shares his passion for jigsaws (or fakes it with admirable enthusiasm).

Since I'm a “time-poor” working mum without the time, patience or the inclination to do any of these things, I'm incredibly indebted to the grandparents for filling in the “parenting gap” in my kids' lives.

And I'm right to be grateful. The findings of the first national survey, led by Oxford University, about the relationships that children have with their grandparents has shown just how much they can contribute to a child's wellbeing. It seems that not only do teenagers value intergenerational bonds but that grandparents' active involvement produces better adjusted adolescents.

In particular, taking part in grandchildren's hobbies and interests was found to be linked with fewer emotional, social and behavioural problems. “Grandparents who get stuck in and do things with their grandchildren are those who bring the most emotional benefits,” says Ann Buchanan, who led the study. “There are huge advantages for grandchildren of this kind of active grandparenting.”

Sixty per cent of childcare provision in the UK is provided by grandparents, saving the UK economy £4 billion a year. It seems that many UK grandparents are playing a role as educators, helping children with homework and providing advice and support.

Grandparents are the ones with whom adolescents feel able to discuss their plans for their future. “They're very supportive and helpful when it comes to what career to take and that kind of thing,” said one teenage boy. And at times of family breakdown and separation, grandparents play an important role in bringing stability.

Look at Barack Obama, who has had a complicated parental situation (his parents had divorced, his father had returned to Kenya and his mother had settled in Indonesia with her new husband). “My grandmother poured everything she had into me and helped to make me the man I am today,” he said as he claimed nomination victory last week.

And yet the grandparent's role is almost invisible in family policy in the UK, according to Ann Buchanan. “The Government needs to rethink the policy implications of this report and provide more support for the important intergenerational relationships.”

More than one million UK children are denied access to their grandparents, either as a result of an acrimonious family split or after being taken into care. Currently grandparents have no legal rights in such situations based on the conclusion of one government report that grandparent-grandchild contact post divorce did not have an “essential purpose or fundamental importance” which would justify an enhanced legal status for grandparents.

Clearly grandparents should neither be underestimated nor taken for gran- ted. But, according to the authors of the report, just loving your grandchildren is not enough. “Only grandparents who got stuck in had this positive impact.”

CASE STUDY Missing out: need for someone older and wiser

Michael Bennett, 29, lives with wife Natalie and their two-year-old son Felix, in London

I'd put it off for years. Finally, a few months ago, I started going through some of the many letters that Anne, my dead mother, kept in three special yellow files.

The one that really got me was written in 1979, when I was not yet 1, by my grandmother - who lived with my grandfather in New Zealand. “My darling, not only will I be thinking of you, but I will be watching over your Michael too. He is such a beautiful baby and I'm sure that he will become a fine man. Because you will make a fine, fine mother.”

My grandmother had cancer and in that letter she was breaking the news to Mum. All my grandparents died before I was 5. I remember meeting only one of them - my gnarled paternal grandfather, a Second World War veteran with an eye-patch and a stick. He smelled of lamb and showed me his medals.

Now I'm a father myself, and grandparent-wise it's a very similar story. Both my parents are long dead. My wife's mother died four years ago. Her father, Carlo, is still around, and he's a lovely old boy who's besotted with his grandson. He comes around to ours most Sundays, and after lunch they go and sit in his car so Felix can “drive”. He comes on our summer holidays, too, and he's hilarious and a fantastic cook. But we rarely ask him to babysit, because he can be a bit forgetful. So we go out less, and when we do it's £8 an hour. If Natalie or I have a business trip, or a work crisis, or fall ill, we have to pay for a childminder to pick up Felix from nursery. There's no love there, and it's a shame that, apart from us, there's no one readily available who

wants to look after Felix because they care for him.

My parents were good parents, but I didn't take notes when they were bringing me up. I wish I could talk to them now, to find out how they dealt with my tantrums, my fixations, my disappointments. Am I getting it all wrong? My parents had both died by the time I was 23. It's also a pretty empty sensation knowing that you're the only one, the last one, and if anything goes awry there's nobody there to pick you up.

Luckily for our son, he'll never really know what he missed out on. I do know what he's missed out on; their love, an added security in his place in the world, and a more comprehensive sense of his provenance than his parents alone will be able to give him. My mother had so many wonderful stories about her mother, and her grandfather, and all her pioneering New Zealand clan. I want Felix to hear the real thing. That's why, at last, I'm going through her letters.

Names have been changed

CASE STUDY: Just down the road - Nanny was an important influence

Lucy Billen, 39, lives with her husband and their ten-month-old daughter, Abigail, in London

Until my parents split up my family lived a few doors away from my maternal grandparents. We lived at 82 while Nanny and Bampy (they were from Wales) lived at 54, close enough that from the age of 8 I could walk to and fro on my own.

As I was an only child with two working parents, my grandparents played an incredibly important part in my life. Mum worked alongside my father in the family business, so I'd go over to Nanny's most evenings. Mum would pick me up from school, drop me round at Nanny's then come and get me at about 7pm. I'd have my dinner and do my homework there, and during the school holidays I'd spend all my time down the road at my grandparents', so we became very close.

My grandmother taught me how to cook - traditional meals such as meat and veg and pies, which still remind me of her. She and I used to bake cakes together - something I still love doing - and she also taught me how to knit. My Bampy turned his whole lawn over to vegetables and used to get me to help with digging and planting, while Nanny and I unloaded the ancient twin tub and put things through the mangle (until I told my mum what hard work this was and shamed her into buying Nanny a washing machine).

My parents split up when I was 11 and my grandmother was a huge source of support. It wasn't an acrimonious split but I still found it hard to talk to my mum about my father. Meetings with Dad were a tetchy subject in our house and I felt I couldn't talk about what Dad and I had been up to for fear of hurting her feelings or being somehow disloyal. Nanny knew both my parents well but wasn't partisan, so I could talk to her about the split without needing to take sides. When things were really raw, that was an immense help to me.

Nanny was funny and could always give a different perspective on things. If someone was giving me a hard time at school she'd give me a hug and some sound advice. And she would always take my side - even against my mum. I could never do any wrong in my nan's eyes and she made me feel secure and loved.

Now I have a daughter of my own I am even more aware of how precious that relationship was. My own mother adores Abby but lives in Spain and the rest of the family is scattered, so there's no one just down the road for Abby. But closeness is not just about physical proximity. Even after we moved farther away from my grandparents they remained a very important influence and it's wonderful to see the bond that Abby and my mother share. They can chat on the phone and I can imagine them texting and e-mailing as they get older.

Some of my happiest childhood memories are of my mother, my grandmother and I going shopping together. The bond I shared with my grandmother never replaced the mother-daughter relationship; it complimented and enhanced it. I hope Abby and her grandma will enjoy the same closeness in time.

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