Great grandparents: Their wisdom helps children handle problems and plan for the future

It said that close relationships between grandchildren and grandparents can protect a child from the worst effects of traumas such as divorce or family breakdown.

Grandparents can also help children whose mothers are not at home because they have to work.

Close relationships between grandchildren and grandparents can protect a child from the worst effects of traumas

The findings from a large-scale survey of adolescents aged between 11 and 16 will be welcome news for millions of families where grandmothers, in particular, have a prominent role in bringing up children.

Working mothers - now the majority of all mothers of young children - increasingly rely on their own parents to look after children.

Single parents, who head more than one in five families, also depend heavily on their own mothers to help.

The Oxford University researchers, led by Professor Ann Buchanan, found that nearly a third of mothers' mothers now provide regular childcare. Four out of ten help from time to time.

Professor Buchanan said the new evidence ran counter to prevailing thinking, which says that grandparents who are heavily committed to looking after children may become depressed and hold the children back.

Her report said: "At times of family breakdown and separation, many grandparents played an important role in bringing stability to their grandchildren. Grandparents-were also found to be important-in times of family adversity and appeared to help the whole family buffer the difficulties."

The survey said that grandparents could help children with their education, encourage them to plan for the future, and advise them in everyday difficulties.

"We were surprised by the huge amount of informal caring that the grandparents were doing and how in some cases they were filling the parental gap for hard-working parents," Professor Buchanan said. "Most adolescents really welcomed this relationship.

"What was especially interesting was the links we found between involved grandparents and adolescent well-being.

"Closeness was not enough: only grandparents who got stuck in and did things with their grandchildren had this positive impact on them."

The researchers found that grandparents were more likely to be involved in the upbringing of children in middle-class districts away from deprived areas  -  and only if they were fit and healthy.

Grandparents became closest when they replaced parents in carrying out traditional roles of mothers and fathers. Some children told researchers that grandparents taught them to read and write, others said grandparents advised on which university they should go to or what to do if they were bullied at school.

Dr Eirini Flouri of the Institute of Education, who also took part in the survey, said: "We found that close relationships between grandparents and grandchildren buffered the effects of adverse life events."

Many grandparents are separated from grandchildren by family break-up and by job mobility which means their own children move many miles away.

The charity Help the Aged has calculated that two and a half million grandparents go for more than a month at a time without seeing their grandchildren.

But the Oxford study said: 'The young people surveyed did not view physical proximity as being necessarily important as they used modern technology to communicate."

The survey involved 1,596 children and teenagers.