We're all familiar with the image of the layabout teenager, but what do you do when this behaviour goes from standing joke to major worry? In this extract from our archives, parenting expert and child psychologist Dr Pat Spungin, CEO of Raisingkids.co.uk, advises.

Raisingkids member's problem
Our 18 yr-old son gets up late every morning, after staying up all night on his computer. He has very few close friends. He's slow to take responsibility for his college work and seems to know how to get away with the bare minimum, with few worries for the consequences. This attitude has spilled over into his new part-time job in a supermarket - he thinks he can hide behind disciplinary proceedings, and he's only been there three weeks!

He takes no exercise at all, apart from the short walk home from college - I drive him in the mornings, as he always gets up so late. He has a tendency to put on weight around his waist and hips which I've told him is bad for his heart. We've talked extensively about health and the need for exercise but he's too idle. Is it too late to stop this laziness and chaotic time management, which seem to be behind all his problems?

Dr Spungin's advice
You and your son are in conflict over his behaviour. I know that you're only acting with his best interests at heart, but you can't make him do what you want. The only thing you can do is find a way of talking to him, so that he will listen to you. How you talk to him is as important as what you say.

For parents of teenagers, the tendency is to nag, get angry and shout. I know... I've done it myself. But I've learned the best way to get through, is by listening rather than lecturing (if you try to imagine your teenager someone else's child instead, it's easier to be calm, and less confrontational). Ask questions and listen to what he has to say. At first it'll be difficult to change your way of relating but stick at it. After a while, your son will want to talk to you.

If he's overweight, he's probably unhappy about it so don't tell him he's fat or lazy. Instead, ask him 'Would you feel happier if you were a bit thinner?', 'Have you thought about how you could lose a bit of weight?' and 'Can I do anything to help?' Maybe you could drive him part of the way to college and walk with him the rest of the way, giving you both a chance to talk. Don't talk about his 'problems' - just talk about whatever you both find interesting, and enjoy each other's company.

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