The problem: Sonia asked for help because her 15-year-old son, Sam, had suddenly become a nightmare. He was fighting with his sister, 13, arguing with his stepfather and wouldn’t even talk to his nine-year-old stepbrother. Sonia, 42, was in despair. What she couldn’t understand was Sam’s timing. After all, her partner, Peter, had moved in three years earlier without any problems.

The bigger picture: The question you always need to ask when someone in a family begins to act up is: “What has changed, what has happened?” Bad behaviour can often be all about making a heartfelt protest against something that hurts, and whatever it is might have slipped beneath your radar. It could be somebody going missing. If Sam’s dad had lost touch, it could have been a relief to Sonia and Peter, and they might not have recognised that Sam felt differently. Or it could be something changing in their relationship — was there an impending marriage or a new baby on the way? If something had occurred to remind Sam about his original family’s break-up, he might be acting up because of it — even if he had coped earlier. Or it could be about issues that were entirely separate from the family and its stepfamily status — problems at school or with friends.

The solution: Sonia and Peter needed to be clear about whether Sam’s behaviour was “normal teenage stuff” or more than that. At 15, young people are going through momentous changes in their physical and emotional development. They may want to establish that they are no longer your little angels but people with opinions and feelings entirely divorced from your own. They often struggle with their sexual feelings and friendships, and where they fit in at school and with their studies.

Talking honestly together, with other parents and Sam’s teachers would help them to sort out whether it was their expectations or Sam’s behaviour that was at fault. Teenagers do quite naturally and normally pull away from parents at this age, and sometimes what passes for surliness is simply an attempt at being separate and self-reliant. Arguments with friends, a first romance going wrong or difficulties at school could be at the bottom of his behaviour. Instead of blaming Sam, I suggested that Sonia should say: “You seem to be having a tough time at the moment. In this family, we don’t argue or fight or ignore each other, we help. So what can we do to make life better for you?” Giving him a firm boundary over his behaviour but allowing him to think over and voice his feelings should give them all a chance to improve the situation.

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