If you are going through an awful period with your teenager, this is a tale of hope. Things do get better. Well, for a little while! One evening last summer I was sauntering home from a local restaurant. It was about 10 p.m.; ahead of me a figure staggered from one side of the road to the other. "Hasn't life changed?" I mused to the husband. "You rarely see a drunk like that anymore. Thank God, the population has become more sophisticated in its drinking."

We continued to reflect and reminisce and got closer to the staggering figure. His gait resembled the proverbial drunken sailor and he was still tippling from a can of lager.

"Look at the state of him. What on earth would we do if one of ours turned out like that?" I said sanctimoniously.

The staggering figure turned and I paled . . . .

Some days later, the door knocker sounded authoritatively and a young garda stood on the doorstep.

"Don't be alarmed," he said understandingly. Then slowly and methodically he related how he had surprised my son and his friend while they were trying to roll a joint. He was not going to press charges because they were so obviously amateurish but he had told them to inform their respective parents and he would be in touch with us.

Friends tell me that I was lucky he got to 15 before our first drink-and-drug encounter, but did I have my head in the sand? Was he suffering hangovers those mornings I called him and he couldn't lift his head from the pillow? And those mood swings - was he looking for a smoke when I thought he was anxious about his study?

I forgot everything I had read about parenting and lost the head. I gave him a few biffs and he gave me a lot of verbal biffing in return. I told him to be in by 10 p.m. and he drifted in at midnight. I told he was grounded and he disappeared for a day and a night. I whinged at him, he bellowed at me and the rest of the family dodged the two of us. Then quite out of the blue he announced he would be embarking on a training programme for the local football team. "The best years of my life are from now until I am 25," he announced in that sensitive way the young have of making you feel that your life is over. "I won't drink or smoke for the next 10 years." And for the last three months that is how it has been. Mr Goody Two-Shoes, as we now call him, eats his steaks, his pasta and drinks his orange juice. He sprays the rooms with air fresheners and does sit-ups and press-ups at every opportunity. He has even stopped bellowing and talks now and then.

So despite what you are going through, it will pass. It's the next phase that worries me.