"It's mine." "Well, I had it first." "So what?" "Hey, get out of my room." If you have more than one child, this bickering will sound familiar. But whilst it's a parent's natural instinct to wade in and sort it out, psychologists say you shouldn't.
"Sibling rows are a normal part of development. In fact, they can be beneficial, so unless blood is being drawn, parents should absolutely leave it to them to work it out," says Dr Mandy Bryon, consultant clinical psychologist at Great Ormond Street Hospital for Children NHS Trust.
Conflict, she explains, can be good for kids because it teaches them how to work things out with other people and siblings are the people they're most likely to practise on. "The sibling relationship is unique because it's the only one in life where you share the same upbringing, resources and lifespan. This makes it an important starting point for developing bargaining, negotiating and social skills," she explains.
But because a lot of things are tolerated, which in any other relationship would not be (pinching, hitting, mean words etc), it can be upsetting for parents to watch, she acknowledges.
"Parents love their children equally, so their desire is for their children to love each other too. It can therefore be horrible for parents to watch their sly, aggressive or negative behaviours around each other. No wonder their natural instinct is to act to step in. It can be so automatic that most parents do it without even thinking."
But equally, it is natural for siblings to want their parents' attention all to themselves and they will vie for it, beating off rivals (siblings) that get in their way. "A lot of parents forget that children aren't normally driven to share. It's a skill they have to learn over the years," she adds.
Of course, there should be limits of tolerance, admits Bryon. "Occasionally, you get insanely jealous siblings, who really do seem to want to kill each other. And occasionally, within normal sibling< relationships, things just go too far.
"But most parents should have a pretty clear idea of where that line between normal and abnormal is by thinking back to their own childhoods, presuming they had siblings themselves. Another way of realising things have gone too far is if there is real violence – not just the odd kick or pinch, but something much more unpleasant."
Parents should be particularly careful of favouring one sibling when it comes to quarrelling, says Bryon. "It's a natural reaction for parents to defend the youngest, for example. But sometimes younger siblings become very clever at getting older siblings into trouble. They will start it, knowing the older one will retaliate and then the parent chastises the older one, saying they ought to know better. It's very common, but if parents catch themselves doing it, they should try to stop themselves."
It's not that parents shouldn't monitor sibling disputes, says Bryon, but being there quietly in the background is generally better than at the forefront of the scene.
Annette Karmiloff-Smith, professorial research fellow at Birkbeck Centre for Brain and Cognitive Development at the University of London, agrees. "The best way for parents to help is to avoid paying attention while the quarrel is on. The less attention they give to the quarrels, the less impact they have. Often parental intervention makes it worse."
Some psychologists - Karmiloff-Smith among them – say parents could talk to each sibling after the argument to discuss what can be learned from it, whilst other parenting experts such as parenting coach Sue Atkins point out that parents can help minimise sibling clashes by focusing on building the "we" mentality of our "family team" and celebrate each child's individual strengths.
"Celebrate the goal your son scores in football and celebrate the goal your daughter scores in netball. It's not a competition to enjoy each other's successes," she says.
But when you do hear your children squabbling, remind yourself that a certain amount of it is not only normal, but necessary. It might seem unbelievable at the time, but it's one of the best ways of learning fairness, cooperation, kindness and caring.
It's not as if siblings will argue all the time, even though sometimes it can feel that way, says Bryon.
"Sibling rivalry is very phase driven, largely because it is so dependent on the development stages of the children," she says.
"Generally, the pattern is that siblings get on better in the early years, move apart in the middle years when they are finding their own friendship groups and have different external influences, then they come together again in the teen and younger adult years."
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