IT WAS a gentle and weary telling-off about table manners, but it provoked a furious and red-eyed outburst from my nine-year-old son. “You don’t know what I go through,” he shouted. Even for a boy with a head and bedroom stuffed with books this seemed dramatic.

But it was true, as a little probing revealed. He was being bullied — not violently but daily — by older boys. His school day was being spent either putting on a brave face or giving his tormentors the angry reaction they craved. I didn’t know what he was going through. Most parents don’t.

Bullied children keep the problem to themselves and sometimes when it gets too bad they kill themselves. According to Tim Field, who runs an anti-bullying website, around 19,000 bullied children in the UK attempt suicide each year. Around 16 succeed.

“Parents are often the last people to find out,” he says. “The child is frightened of reprisals, but also — and this is key to the sort of child who often gets bullied — he or she does not want to cause pain to parents.”

Many bullied children suffer in silence because they know that telling someone can make it worse. They fear that if they tell a parent, there will be scenes at the school or scenes with the bully’s parents. Parents need good emotional radar and a softly-softly approach, according to campaigner Liz Carnell, whose son had a tooth knocked out at his first secondary school in Harrogate.

“Sometimes parents get a gut feeling. Sometimes they notice a change in social behaviour, such as fighting with siblings, being defiant to parents or not wanting to play with friends. Then there are children who stop eating or start wetting the bed.

“The important thing is not to grill the child. It’s tempting because you feel desperate. I know what it’s like: I had a 12-year-old son who was telling me he didn’t want to live. You need to be very subtle, asking them how a particular lesson went or who they played with. Take time to talk and you will build up a picture.

“Enlist the help of family or friends. Often a child will tell a grandparent or a cousin because they have no fear that person will complain to the school,” says Carnell, whose voluntary online help service receives more than 8,000 calls a year.

When she complained to the school, the head told her there were vacancies elsewhere and the problem lay with her son. Many parents, she says, get the same response, the impression that somehow their child is the type who asks for it.

Field, who co-authored Bullycide: Death at Playtime, believes some are more likely to be bullied, but it’s not the wimp or the geek. “People targeted are sensitive, honest, creative, have high emotional intelligence, a strong sense of fair play and high integrity. They often have qualities of maturity and decent values. They tend to be emotionally mature, believing that conflict is best dealt with by negotiation. So when the child is goaded into hitting out and gets blamed, he feels he can’t win.”

This was one of the things that happened to my son. Having told the bully to buzz off one Monday morning, for the rest of the week he was pursued with “buzz, buzz” being hissed in his ears. Finally on the Friday he snapped — he’s big and strong — and shoved the bully into a temporary builder’s door. An alarmed teacher told my son off — but did not tell off the bully.

Eventually, the deputy head tackled the problems and things have improved. But many parents meet a brick wall. “There are lots of heads who simply deny there is bullying in the school. If you meet that response, it’s probably best to move to another school,” says Field. “Legal action is an option: the school has a duty of care. It is difficult to know who the employer is, but it is generally held to be the local education authority.”

That’s the route Carnell, a journalist, took, accepting a £6,000 out-of-court settlement from North Yorkshire County Council in 1999. She advises trying other means first.