Many siblings, when they get together as adults, joke about which child was loved the most. But is it really a joke or is there an edge of truth that still rankles us?
In one study, researchers asked adults whether their mom played favourites when they were kids. Close to 85 percent of respondents perceived that she did.
But surely once we move out of the nest, our annoyance regarding sibling favouritism subsides? No so. Upset from perceived favouritism appears to be long-lasting.
It is likely that we will fret long into adulthood over why a particular sibling got a better deal than we did.
Is sibling favouritism real, or perceived?
It turns out parents do behave differently with their children and, of course, children have their different thresholds for noticing these differences.
Researchers have studied favouritism both by observing children as they interact with their parents and by asking children and their parents to report on their interactions. How often do the parent and child laugh or play together? How often do they fight or argue?
These ratings are then compared across the different siblings to determine if one child receives more positive or negative attention than the other.
One of the reassuring findings from these studies is that when the differences in how siblings are treated by parents are small, it has little to no consequence.
It is only when the differences are large that we see links to children’s health and relationships.
Parental stress plays a role
Research on all different kinds of relationships shows us that a big part of how we get along with others is about the fit of personalities. We find one person easier or more interesting than another. The same holds for parents and children.
Although most parents love and nurture all their children, they will inevitably find that they are more in tune with one child than another. One child is perhaps a bit more social; another is more ready to anger, a third finds learning easier.
These differences in how parents treat siblings have a basis in children’s genes. Parents treat identical twins, who share 100 per cent of their DNA, more similarly than they treat non-identical twins, who share about 50 per cent of their genes.
The more the personalities of siblings differ, the more their parents treat them differently.
Another driver of parenting is, of course, a child’s age. Parents interact with and discipline their children based on changes in developmental capabilities as they grow. Age and personality explain some of the differences in the parental treatment that children perceive.
But while age and personality play a role in why one child gets more from a parent than another, over and above this are issues of parental stress. When parents experience financial strain, mental health problems or partner conflict, differential parenting or sibling favouritism becomes more marked.
Impacts on physical and mental well-being
Unfortunately, perceived favouritism can create a divide between siblings. It is associated with siblings feeling less close to one another, both in childhood and adulthood.
This finding has been established for both perceived, as well as observed favouritism.
Popular wisdom suggests that the favoured child receives benefits from their special treatment. While this may be the case when favouritism is slight, research suggests that none of the siblings benefit when it is more marked. That is, when favouritism is considerable, it is associated with all siblings showing less physical and mental well-being.
Reasons for this are not currently clear. It is possible that children are activated by injustice. Or perhaps even when they are favoured they fear falling into the realm of being disfavoured.
But most reassuring for parents are the findings that parental explanations for why they are treating siblings differently really change the experience for children. Explanations that focus on their different personalities, ages or needs are associated with lower levels of distress for children.
Five tips for fairer parenting
Be aware. The first step is to be aware that it happens, and to seek out help or support from partners, family members, friends or health professionals — to try to understand why it happens. As a reminder, playing favourites is more likely to occur when your stress levels are high.
Listen. When your child complains or you see fights between siblings in which they mention one getting more than another, try not to discount it. Be receptive to the child’s feelings and think about why they might be feeling this way.
Provide an explanation. Sometimes, children do need to be treated differently, like when one child is sick, hurt or has special needs. When this happens, explain it to avoid any misunderstanding.
Avoid comparing children. While it may be a natural tendency to say “why can’t you be more like your sister?” this sets up an unfair comparison. Try to focus on what each child does well, without pitting them against one another.
Carve out individual time for each child. As much as possible, try to find 10 minutes each day to spend one-on-one with each child so that each has your full attention. Do any activity that they love to do with you.