We all know how our relationships with our parents may shape the kind of person we become, and our own future romantic liasons – but what about the relationships we have with our siblings?

As everyone who has a brother or sister will know, dealing with your familial other halves can be complicated. Dynamics can be set early on, roles assigned and, if parents aren’t careful, resentment between siblings vying for their attention and praise can fester for years and spill into bitter rows well into adulthood. 

This powerful yet woefully-under researched relationship is the focus of The Secret Life of Brothers and Sisters, a new TV series starting tomorrow night. The latest in Channel Four’s The Secret Life Of... series, it follows seven pairs of siblings and peers on a three-day camping holiday, with scientists observing how they negotiate and interact in the absence of their parents, with fascinating - and often hilariously funny - results. 

The sibling is typically the longest-lasting relationship of our life, so how does it shape us, and how can parents ensure close and happy relations among their offspring?

Competition among siblings is inevitable

No parent has infinite time or resources, so each new addition to the family is perceived as a threat by the others. Furthermore, the more similar children are—in age, gender, or temperament—the more likely it is that they’ll have the same needs at roughly the same time, and, therefore, the more intense the rivalry and competition between them.

The need for parents’ exclusive attention is so powerful that the mere presence of a parent may trigger competitive behaviour. Nick, one of the parents in the new series, says: “Harry and Charlotte can be playing together happily and imaginatively, but if I walk into the room, they immediately start competing, arguing or trying to outshine one another.”

The harder they fight as children, the better an adult relationship may be

The stronger the emotions — negative or positive - that one child feels towards a sibling, the closer their relationship is likely to be in the long run. If your children are constantly arguing, you’ll also have more opportunities now to teach them social and problems solving skills that will allow them to get along well with friends, work well in teams, and know how to create and accept compromise. These skills, known as Emotional Intelligence, are closely correlated with good mental health, a positive outlook on life, and even with greater success in the workplace.

The right parenting can create lasting bonds between siblings 

Parents should look for and encourage those qualities that distinguish each child, the qualities that make each one unique. If each child feels equally valued, and not constantly compared to their siblings, they’ll have little need to compete with or feel antagonistic towards the other children in the family. One warning, however. Older children will quickly learn that a sure way to win parental praise is to help care for their younger siblings. That’s great to a limited degree. However, if that’s the only thing parents praise in their older children, it can lead to an over-anxious need to please authority figures in the older child, and a sense of being over-managed and stifled in the little one.

Siblings who play together, stay together

Shared experience, particularly new adventures and challenges, strengthens bonds between siblings. That’s why it’s so important to have family holidays, regular family meals and family 'rituals’ such as a special way of celebrating Christmas or New Year - even if these occasions are punctuated by heated debates. 

Siblings who are encouraged to work together to achieve a common goal are also more likely to be close as adults than siblings who feel pitted against each other. An example of this in the new series is when the children are challenged to climb over hay bales, something the younger ones can’t manage without help from their older sibling. This teaches them the value of co-operation (resulting in bonding) over competition. Parents can promote bonding by rewarding cooperative and generous behaviour between siblings whenever they see it. Explain in specific terms why you’re so pleased with their behaviour. If children learn how to cooperate and if they learn that this is guaranteed to win your approval, they’ll be less tempted to try other (more divisive) ways of interacting.

Know when to step in

Wherever possible, let your children try to solve the disagreement themselves. We learn better by trying out possibilities than by being told what to do. However, monitor the situation and be ready to step in if anyone looks to be in danger. If a disagreement ever escalates to the point where this is necessary, children should be taken through the following steps. First, everyone must calm down. Ask them to sit or stand apart from one another and take some deep breaths. This may make them laugh. That’s fine—laughter is a great tension reliever. Next, ask each child to state their grievance — but then, to describe as best they can what their sibling is feeling. Stepping outside of our own viewpoint teaches compassion and brings people closer together. Third, ask each child to come up with at least two solutions. This introduces the idea of compromise as opposed to winning and losing. 

What siblings gain here is priceless, and will enhance their relationship as adults, as they will develop confidence in their ability to solve problems, and increasing closeness to the sibling they understand a bit better.