Using an online social networking site allowed my niece to keep all the relatives informed on the safe arrival of her baby girl.

But the same internet site also left my friend's teenage daughter distraught when she found an anonymous, offensive comment written about her.

She had been using the site as normal when she stumbled across six cruel words written next to a picture of her.

She was devastated. Her parents were, unlike in normal situations where a child is hurt, helpless.

The words which caused so much distress are too offensive to repeat here. They weren't written as a comment so couldn't be deleted; all this girl's parents could do was offer comfort and report the picture to the administrators of the site.

The strongest emotions when having a child is love and the need to protect. All parents know they have to strike a balance between wrapping their offspring in cotton wool and allowing them to experience life as safely as possible.

Sometimes sensible instructions will help keep them from harm – when they are young, simple ones such as don't put your hand on the hot oven as you will get burnt or don't run on ice or you'll fall over, usually suffice.

As they grow up, there are the dangers of life to learn from crossing the road to not talking to strangers.

But as they become teenagers it is so much harder, particularly as they begin to enjoy the freedom of cyberspace.

They have something we didn't have as children which is the ability to interact with their friends morning, noon and night via the internet, to share moments in their lives instantaneously. However, there is a downside even when they are careful to keep their details secret and subscribe to privacy options.

As it happens with this dreadful experience, there was also a positive side. For her friends, who had also seen the comment, were fast and furious in their condemnation online, posting their own comments attacking the anonymous sentence.

For once friends and parents were speaking the same language – the overwhelming message to this teenager was that this had been an outrageous thing for someone to do but it also showed her she was loved by many, many people; perhaps more than she actually realised.

Encouraged by the support she has received, this teenager is moving on. Of course, the words stung but she realises it is only a coward who doesn't put their name to an insult and is still using the internet as a means of communicating with her friends.

Reading (and re-reading) the words of a bully is as painful as a verbal onslaught and as parents we need to realise that children need to be taught to cope with cyber attacks as well as those in person.

Just as there is good and bad offline, it can be found online too.