For the past year, I have been living with a little person that I have not known - my eldest son, now 12. Of course, this time coincides with his starting secondary school, but as far as settling into school is concerned he has coped admirably: he's interested, conscientious and well-behaved.

The person who arrives home, however, has been sullen, 'bored', dissatisfied and extremely disruptive, to the point where sanctions no longer have any effect and the resulting behaviour upsets the entire family.

Small signals of adolescence have cropped up, greasy hair, armpits that require more than a once-over, and the odd blackhead collection. Other than that he is not a big boy and looks like any other child.

Admitting defeat is not one of my traits and I decided to attempt some kind of programme on my own to begin to 'like' my own child, in the knowledge that if I did not do something soon, it would be too late.

Yesterday my efforts paid off. After a day of the usual battles, I went upstairs to put out his light for the night.

'Mum,' he said, 'I feel awful, and embarrassed because I've got hairs on my willy.'

'Don't be silly,' I said, 'nobody has hairs on their willy.'

'Look, I'll show you.'

And so he did. He didn't have hairs on his willy, but he did have hairs around it. He started to cry. I gave him a huge hug, and we had a long chat.

He was, and is, full of fear. He has obviously been wanting to talk about this for some time, but he has been too embarrassed.

I feel guilty, because I had no idea. I have looked discreetly when he was in the bath, but I hadn't noticed anything different happening.

There's no point in excuses. The reality is that I should have brought this topic up before now.

I have talked about the usual reproductive topics; as a family, we discuss sex quite openly. But other than chucking an appropriate book in his direction I have not discussed the finer details of puberty with him.

In the car, on the way to school, I had the opportunity to talk with him again. He wondered if he'd ever be able to play with all his cousins again, the kind of games that he is used to - running wild in the Welsh countryside, making dens, getting very dirty - or whether soon, all they would do when they got together would be to talk about school and girlfriends and boyfriends?

My heart went out to him. I told him that other boys in his school are probably going through the same thing, and asked him whether he ever talked to them about it. He said that he just couldn't, he was too embarrassed.

After having delivered him to school I began to compare all this to my own adolescence, some 22 years ago. Something occurred to me which seemed so obvious.

Adolescence amongst girls is inescapably visible. At my school, you started wearing a bra, and if you didn't (like me), you put elastic where the other girls often pulled to see if you had started wearing one or not. As for periods, we always knew who was and who wasn't because games and swimming lessons were frequently missed because of period-related excuses.

Because everything was already out in the open, it was discussed. By comparison, there is a painful silence in my son's adolescent world.

I wonder how many of those 11- and 12-year-old boys are going through that same painful silence, and I wonder how many parents are close enough to their teenage sons to appreciate the burden they carry. It is not easy to get close to an adolescent son, and just because you love them doesn't mean you like them.

People often say that a major difference between men and women is that women feel they can express their feelings and men feel that theirs have to be suppressed. Perhaps this time in adolescence is when those differences are fostered and perhaps it's time that we made an effort to understand our adolescent boys and open lines of communication.