According to family systems theory, a family is regarded as an organized whole and relations within this system are interconnected. However, it is not clear to date whether the interparental and the sibling relationship are associated and, if such an association exists, whether it is positive or negative. Previous findings on the associations between the interparental and sibling relationships are inconsistent and there is as yet no pertinent review or meta-analysis. Therefore, this systematic review and meta-analysis set out (1) to aggregate previous studies investigating the links between the interparental and sibling relationships and (2) to examine potential moderators in this link. Based on 47 studies reporting 234 effect sizes (N = 29,746 from six nations; 6–12 years; 49% boys), meta-analytic results suggest a small positive correlation between interparental and sibling relationship quality (r = .14). Only the percentage of male children in the sample moderated this effect. Sex composition of sibling dyad and source of publication affected whether positive or negative associations were found. The findings support a growing consensus that family relations do not function in isolation, but are mutually interdependent, which should be considered in clinical practice.

No abstract

Attention-deficit/hyperactivity disorder (ADHD) is one of the most common mental disorders in childhood and adolescence. The child’s ADHD symptoms are associated with increased stress levels for parents. Previous research has shown that parenting stress has a negative impact on parental relationship quality, but those negative effects can be mitigated through the couple’s positive dyadic coping. However, these associations have not yet been studied for parents of children with ADHD. Therefore, this cross-sectional online study was aiming at investigating whether dyadic coping moderates the link between parenting stress and couple relationship quality in parents of children with ADHD in comparison to parents of children without ADHD. Data from 446 parents of children aged 6 to 16 years (clinical group: n = 265 parents of children with ADHD; control group: n = 181 parents of children without ADHD) were analyzed separately for both groups using moderation analyses. Results showed that negative dyadic coping significantly moderated the association between parenting stress and relationship quality in parents of children with ADHD, such that the link was positive, when negative dyadic coping was low. No comparable results were found in the control group. With respect to positive dyadic coping, there were no moderation effects in either group. The findings indicate that stress in parents of children with ADHD may have a favorable effect on the couple relationship if negative dyadic coping is minimized. Therefore, reducing negative dyadic coping could have a beneficial effect on the parents’ relationship quality and ultimately on the overall family climate.