The lifelong effects of 'the favourite child'

Most parents won't admit it, but a surprising number have a 'hidden favourite' and the way they treat that child compared to their siblings can have long-lasting impacts on their mental health as adults and on family relationships.

My siblings and I always knew when our middle brother was coming to visit my parents: my mother would put out little bowls of prawn cocktail, as a special starter. 

"Prodigal son," we would protest, slightly miffed that the rest of us never had this kind of privileged treatment. The official explanation was that he didn't come over for Sunday lunch as often as the rest of us, but that still didn't really seem fair.

In truth, despite the prawn cocktail, I did not think my parents had any favourites. I grew up as one of six siblings in a working-class family in north London. Of course, my brothers, sister and I all had different roles and jobs in the family, but the reasons just seemed practical. As the youngest, for example, I was always the one to go fetch things for my parents, maybe because they thought I had lots of energy anyway. My sister was usually the one to go shopping, because she could drive. It was a busy house and to add to the mix, we also owned a dalmatian dog, Sheba. 

Overall, it all felt quite even-handed to me. But last year, at a family gathering, one of my brothers blurted out that he thought I was my father's favourite.

My sister seemed a bit surprised by that. And I realised that there might be more to the story I had told myself – of our parents not really having favourites. I wondered how people in my and other families really experience these dynamics, and how they might shape us in the long run even if we're not fully aware of them. 

Research suggests that parental favouritism is surprisingly common – and rather than being just a quirk of family life, can actually be very harmful. It occurs in around 65% of families, and has been identified and studied across many different cultures. As widespread as it is, it can damage children's wellbeing across the lifespan, from their childhood into middle age and beyond. It is considered such an important factor in a range of emotional problems that psychologists have a name and acronym for it: "parental differential treatment", or PDT.

However, as in my exchange with my brother, siblings in the same family may disagree over whether their family is even affected by it. That's because feeling less-favoured can be very subjective, says Laurie Kramer, a professor of applied psychology at Northeastern University in the US. "It is the experience that people have, that a parent prefers another child to them," she says. "This could be by devoting more time, attention, praise, or affection. Possibly asserting less control, so that they may enjoy fewer restrictions, be subject to less discipline or even punishment."

Importantly, not everyone in the family may see it that way. "This may not be the same observation that the other sibling encounters and may be different again for what the parent believes they have engaged in," says Kramer. 

For the person who feels like they are treated as second-best, the consequences can be profound. Research suggests that from an early age, children are aware of differential treatment, such as parents showing more warmth to one sibling than another. Such perceived parental favouritism has been associated with low self-esteem in children, as well as childhood anxiety, depression, and behavioural problems, including risky behaviour. There may also be a knock-on effect on emotional wellbeing that causes other, more indirect problems. Researchers in China have, for example, shown that parental favouritism is a predictor for mobile phone addiction in adolescents. In a small Canadian study of eight homeless teenagers, seven said they felt that their parents had favoured a sibling over them, while they had always been the "problem child", and that this had contributed to the breakdown of family ties.

While this final study is too small to draw wider conclusions, it highlights just how far a child's experience of favouritism can potentially go.

The mental health impact may persist into adulthood, with maternal favouritism for example being associated with higher depression scores in adult children. The bias itself may also continue in later life, with parents still playing favourites with their adult children. And while the parents rather than the siblings bear the responsibility for this, favouritism can harm the sibling bond over the life course and increase tensions and conflict between siblings. This is especially worrying as having good relationships with our siblings is important for our lifelong health and happiness.

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In Kramer's view, they may not doing so intentionally, and are likely not even aware they are. "Preferential treatment may begin for parents due to one child being easier to parent, they may relate to that child more, see similarities between them and the child," she says.

Her research on adolescents and their parents has shown that families don't tend to talk about this, which makes it even harder to clear up any hurt or misunderstandings. 

"If these situations were addressed in a sensitive manner, where no one feels they are being blamed or that it is their fault, you can have more open conversations on all sides to understand," Kramer says. Parents could, for example, ask why the child feels they prefer a sibling. "If a parent listens [and] then provides a reason for the differential behaviours to a child, that can work wonders." The child may realise that there is a practical reason, and that it's not about the sibling being loved more.

In my family, we had never broached the subject of favouritism, either. But after my brother's throw-away comment on me being the favourite, I decided to find out more.

First, I asked my brother why he had made this comment. He replied that our father had once told him off for scaring me with the Mole from the Thunderbirds TV series – a kind of giant drilling machine – and making me cry. I have no recollection of this moment, maybe as I was not on the receiving end of the telling-off.

As my siblings and I talked more, we remembered my mother sometimes giving our eldest brother preferential treatment, probably because he was her firstborn. Meanwhile, our father often praised our middle brother for being shrewd, a quality he admired, and which they both shared. And then there's that prawn cocktail that comes out when our middle brother visits, of course.

They are small differences, but it's easy to see that they might have amplified into something more and could even have led to resentment. It's possible that the impact was watered down by the fact that there are six of us – and the five who didn't always get the "prawn cocktail treatment" could joke to each other about it. And we all still got to enjoy the prawn cocktail when my middle brother visited. Imagine a family with only two grown children, and one is served a prawn cocktail lunch, while the other always gets the plain option: it would probably feel very cruel to that child, like being punished or cut out.

Megan Gilligan, an associate professor of human development and family science at the University of Missouri, worked with Jill Suitor, a professor of sociology at Purdue University and Karl Pillemer, a psychology professor at Cornell University, on the Within-Family Differences Study in the US, a longitudinal project funded by National institute of Aging. The project has tracked different families for two decades in order to better understand relationships between the generations. As part of the study, the researchers asked mothers and fathers a direct question about favouritism – for many, it was the first time they were asked about it at all.

The question was: "To which of your children do you feel most emotional closeness?" After a slight deliberation, a high proportion of mothers (75%) then named one of their children. The rest chose none, or said they felt equally close to all of them.

They were also asked who they felt more disappointment and conflict with. The answer had consequences across the lifespan, with the child picked early on as "disappointing" then also treated that way later on.

Birth order played a role in some aspects of favouritism, but perhaps not as much as is often assumed. "In adulthood, [research does not] find this to be an overwhelming predictor of favouritism," says Gilligan.

Specifically, my guess that the first-born would naturally be picked as the "golden child" is not backed up by the scientific research. For emotional closeness, last-born children are actually more likely to be chosen than the middle or first child, Gilligan says. But the strongest predictor for emotional closeness were the parent's feelings of the child being similar to them.

Gilligan also highlighted the real damage that can result from differential treatment, which showed up in the longitudinal story, such as poor sibling relationships, the less-favoured sibling feeling more inadequate about themselves, and having a less positive relationship with the parent.

Being the "golden child" can also come with pain. "You might expect being a favourite child to come with many benefits, however, it can also cause emotional distress for adult children," she says. "We have found favouritism to be associated with higher depressive symptoms for favoured children. We believe that this is because being a mother's favorite child creates conflict in their favoured children's relationships with their siblings. We have found that that this tension with siblings in adulthood is consequential for psychological well-being."

It may also lead to an unequal burden later in life. When a parent eventually requires care by family, they often turn to the child they feel was the favoured one, she says.

And while favouritism can haunt us even as adults, our experience of it can change subtly as we age. Gillian authored a review of studies on the impact of favouritism across the lifespan, from very young children to grown children now in their 60s or older. She found that there are differences in how it shows up at different stages. For younger children, favouritism may be more about how much time parents spend with them compared to a sibling. For adult children, it may be more about unequal financial support.

The answer is not to treat all of one's children exactly the same, says Kramer. "It is impossible to treat kids the same in every situation, and neither do children want this," she says. "They want to be understood for who they are, their age, interest, gender, personality." Still, being more self-aware can help parents avoid consistently causing unfair situations, she says. This is especially important as children may learn the pattern of favouritism, and as adults, apply it to their own parenting style and relationships: "Unless we are aware and take action to break that transmission, we are likely to engage in the same behaviour."

The idea of learning certain biases from our parents, certainly rings true. My mother would always plate up slightly larger portions for my brothers, as they were seen as "growing lads". My partner has noticed that when I dish up our evening meal, I do the same, serving him more than myself.

I don't feel traumatised by the slight differences in the way my siblings and I were treated as children, and perhaps, even today. We are close to our parents, and to each other. Looking back, our pet dog, Sheba, was possibly my dad's real favourite.

But becoming more aware of some of these differences in treatment, and how they've shaped my own behaviour, has made me see a few things in a different light. For a start, I might try serving myself larger portions in the future – and I don't wait for my brother to visit to treat myself to a prawn cocktail.

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