How do your children get on together? Do they go from being the best of friends to arch enemies in the space of half an hour? Do you find yourself stepping in to break up fights or arguments, only to find they then gang up against you to defend and support each other?

This behaviour is inevitable and perfectly normal. In fact research suggests it’s positively beneficial. But too much bickering between siblings can be wearing for everyone. While rivalry may be at its peak in the early years, be prepared for your children to be competing into their teens and in some cases even into adulthood. The good news is there is a lot that parents can do to influence relationships between their children. And with the summer holidays approaching, thinking about how you can achieve some degree of harmony might prove useful.

Why do they argue - and how is it beneficial?

Siblings have a unique relationship. They share the same environment, the same genetic make-up (if they have the same parents) and have to learn to share their most treasured possession - usually their mother. With a brother or sister, a child usually feels a sense of security and freedom that allows them to test out all sorts of emotions that they wouldn’t dare exhibit with anyone else. They can scream and fight with a sibling in a way they can’t with a friend. This helps children learn the consequences of losing their temper, and getting back as good as they give. They learn to take criticism without it destroying their self confidence. It also enables development of social-cognitive skills as they learn the ‘arts’ of negotiation, manipulation and other means to get their own way. And they learn about loyalty as siblings tend to be critical of each other, but defensive when a sibling is attacked by an outsider.

Their shared life experience means siblings tend to have stronger bonds in adulthood and be a good source of support even if they don't consider themselves to be particularly close.

When do problems usually start?

Often right at the beginning with the arrival of a new baby in the family. Studies show that the way a mother interacts with the new child will have an effect on the future relationship between the siblings. It’s natural to feel protective but if you are very protective with a new baby, the older child is more likely to feel resentful and show aggression. Preparing your older children carefully for a new arrival is important, as is spending time alone with each older child once the baby’s born. This can be difficult and you are likely to need to ask for help. Organising for someone to look after your baby for an hour, or taking an older child out for treats, is a good idea.

What about when children are big enough to fight?

As children grow up, this is bound to happen at times. Letting them sort out their own disputes is best as it helps develop their problem solving skills. Step in only if they are not resolving the argument or if there is an obvious inequality - for instance one child has something that’s being used as a weapon. In that case a parent should act as the arbitrator - not blaming one or the other, but asking what is going on and how it started. Getting clear answers can often be difficult though.

Get them to apologise to each other. If they won’t, try saying: ‘Well I’m unhappy about that’, and walk away. Usually they sidle up to you later to make amends. It is also worth trying to encourage appropriate behaviour by suggesting after the incident what your children could have done instead. You are aiming for assertiveness not aggression.

How do you handle general squabbles?

Letting children take turns at being ‘first all day’ is a tactic that often works well. A lot of squabbles happen because each child wants to be the one that sits in the front of the car (if big enough), take the last chocolate croissant, choose the story, sit next to mum, etc. The ‘first all day‘ strategy is preventative. They learn that they get their own turn eventually and also, very importantly, they learn to cope with the horrid feelings of seeing their sibling getting the best bits because they know that it's soon over and it’s their turn the next day.

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