Brothers and sisters within a family, with the same parents, experience their upbringing differently. As well as the impact of their own negative experiences, the way siblings experience their upbringing also plays an important role in anxiety and depression. This is the conclusion reached by Marie-Louise Kullberg in her PhD dissertation. Defence on 21 September.
Why does one child within a family struggle with psychological complaints, while their brothers or sisters do not, even though they are growing up in the same environment? This is one of the research questions studied by Marie-Louise Kullberg (Clinical Psychology). 'The answer to these kinds of questions is crucial to better understand developmental differences and further tailor our prevention and treatment interventions to each family or individual.'
Studies that include several family members are rare because they raise both practical and statistical challenges. ‘In one of our studies we focused on a large group of adults with symptoms of depression and/or anxiety and their brothers and sisters with and without anxiety or depression (N=636, 18-78 years). This research population offers the unique opportunity to answer questions about similarities and differences between siblings in terms of their psychological complaints, by using questionnaires.
Upbringing is not a one-way street
Parents clearly have an influence on their children, but the question is whether that influence works in two directions: the behaviour of the child can also influence the behaviour of the parent. We therefore looked at how psychological complaints experienced by parents and children impact the interactions within the family, and measured this using a parent-child interaction task in the lab. Our study included 137 Dutch families, with 94 fathers, 125 mothers and 224 of their children, all of different ages, ranging from 7.5-65.5 years. In all the families there were to a greater or lesser extent issues of emotional mistreatment or neglect.
Individuals with internalising problems – such as anxiety and depression symptoms - during the past six months were found to be less negative towards their father. Externalising complaints – such as behavioural and aggression problems - were found to have a particularly negative impact on father-child interactions; both fathers and children with externalising problems were found to express more negativity towards each other. Individuals with externalising symptoms also tended to receive less warmth from their mothers. No associations were found between fathers' and mothers' internalising complaints and parent-child interactions, nor for mothers' externalising complaints.
Families in the corona pandemic
We also studied the parenting experiences and mood of 34 Dutch adolescents and 67 of their parents in a two-week diary study during the first lockdown of the corona pandemic. Overall, we found that parents' negative mood had increased compared to the period prior to the pandemic. This was not true for adolescent mood, nor for the level of warmth and criticism from the parent. It was notable that these outcomes varied greatly from family to family, indicating that intervention and prevention tailored to each family is essential.
Applying the finding
In current treatment guidelines for common mental health problems in adults, most therapies are focused on the individual and are complaint oriented. 'The findings of this research show that it is time to zoom out from the individual to the systemic level in both research and clinical practice,' Kullberg advocates. For instance, if someone comes into the consulting room with symptoms of depression and if there are also negative parenting experiences in the family of origin, it may be advisable to use a complementary systemic approach focusing on past and current family relationships.