IT USED TO BE psychopaths. They lurked under the bed, waiting to attack a fearful nine year old - as night after night, we'd chat about what a psychopath might look like, or how he'd fit under the bed.

His image was always blurry, but her fear was very real.

Right now, it's vampires, and they hide in the television room. Until mother has run a complete vampire check on the room, the eight year old can't settle down to watch telly - where the vampire fear started in the first place.

You might think of it as home sweet home, but to your child the place you live might be a House of Horrors. And if he or she has nightmares on Elm Street, if your children's fears make their lives miserable, and yours inconvenient, what should you do?

Everyone can sympathise with the small child's fear of the dark, but what if your seven, eight, nine year old insists on having a bodyguard every single time she goes upstairs to the toilet, or to her room to get a toy? If nothing will persuade him to go to sleep by himself? If he sleeps with a hurley to ward off burglars and grips it as he crawls into bed with you?

You're a modern parent. You've examined your child and your conscience to see if your child's fears signify hidden, unaddressed insecurities, as advised by consultant clinical psychologist Dr Tony Humphreys, writing here two weeks ago.

You've never, ever, ridiculed a child's fears, always talked them through and held their hands and waited . . . waited . . . waited . . . for them to pass. Just what is it you're doing wrong?

Childhood fears of monsters, witches, ghosts, the dark etc are pretty normal in three to six year olds. But fear is a complex subject and falls into several categories, says Andrew Conway, senior clinical psychologist at the Mater Child Guidance Clinic in Dublin. There are normal childhood fears, which cease to be quite so normal if they persist in children aged six upwards. Then there are phobias, which in a child can take various shapes, e.g. serious school refusal(usually a form of separation anxiety).

There are fears triggered by real events - if your house is burgled, for instance, children may harbour residual fear long after parents have come to terms with the trauma, and a sensitive child may worry if a close friend's or neighbour's house has been burgled. And there is fear of death, which typically, starts at age 10 or 11, Conway says. "They might have gone to a funeral; some children will brood, might go off their food."

While reassurance is the key word, being over understanding can prolong a child's fears: if you don't gently persuade a young child to cope little by little with, for example, a fear of the dark, you may find yourself on bodyguard duty as your eight year old visits a quiet part of the house. ("Is it witches you're afraid of, pet?" "Duh, like I believe in witches I'm just afraid somebody will jump out.")

Yes, isn't it ironic? According to the experts, you confirm your child's fears, appear fearful yourself, if you accept them too fully. If the fears do linger on into late childhood, your job is to train the child out of his fear little by little.

Psychiatrist and TD Dr Moosajee Bhamjee recommends first of all avoiding certain films and stories, and increasing daytime self confidence by getting them involved in activities away from parents.

Andrew Conway says you have to work on "systematic desensitisation". If your child can't sleep in the dark, leave a light on, then turn it off when he or she is asleep, and congratulate the child.

"Don't ever say `no lights'. Reassurance is the buzz word."

NATURALLY, you do have to look at the role of television and videos, which quite certainly will affect some children. There are families who didn't get a night's unbroken sleep for a year after letting a child watch horror comedy Hocus Pocus, or Gremlins (furry, sharp toothed, and very savage).

But children, like adults, vary in their level of sensitivity, and you do need to spend some time watching with children to get a feeling of what will and won't worry them.

Usually, it's not the predictable like the psychopaths under the bed, which were traced some years later to a Neighbours sub plot that an adult would have blinked and missed.

And it's not always television. One mother remembers her four year old son's terrible distress after his childminder's seven year old sister had told him in bloodcurdling detail one of those "There was a house ... and in it was a bloody hand" tales.

But visual images do have power: why else will a child whose favourite - fairy story was the dark and disturbing Rapunzel, and who loves the stranger bits of Roald Dahl, be so susceptible to a two minute glimpse of a vampire, found while channel surfing? (He's tall, very white face, sharp teeth and a long black coat. Hell, I'd be worried.)

Blaming television and ghost stories might be a little too glib, though. You must think hard about the source of the fear, must never assume it's just a bad habit. Your child's fears might well indicate that he or she is suffering some kind of stress, is being bullied, for example - "and that's when the whispering they hear on the stairs, he noise in the garden is a manifestation of an unexpressed worry" Conway says.

He suggests that perhaps you could put 10 or 20 minutes a week aside for a "worry list", a time to talk to your child about all the things that are bothering him/her.

Family stress as the root of the fear cannot be underestimated either: parents often assume that because they're coping with various major problems fairly stoically that everything is under control. But psychologists keep emphasising that stress affecting parents will affect even the youngest child, though exactly how may not be obvious to a parent.

Most fears can be managed sensibly, Conway says. But you do need to be alert to those that have anxiety disorders lurking beneath them, that may signal the early emergence of a psychological illness. If you think your child's fears are heading that way, you should look for professional* help quickly, Conway suggests.

Some children, for example, get obsessions and compulsions that may be the beginning of an obsessive compulsive disorder. If you see that a child is spending undue time trying to prevent something happening by performing certain rituals, if you find you're waiting in the car longer and longer each morning because your child is spending five minutes or more washing, he or she may well need clinical help."