Associations of sibling relationship quality and emotion regulation with child functioning in families with parental cancer

In families facing parental cancer, children have an increased risk for impaired psychosocial functioning, such as lower quality of life and satisfaction with life, and increased posttraumatic stress symptoms (PTSS). These outcomes are likely affected by both dyadic and individual factors. The aims of the current study were to examine (1) the associations of sibling relationship quality (i.e., warmth and conflict) and emotion regulation problems with child functioning (i.e., quality of life, satisfaction with life, and PTSS) in families facing parental cancer; and (2) whether emotion regulation problems partially or fully mediate these associations. Our sample consisted of 161 children from 82 Dutch families facing parental cancer (84.6% maternal cancer). During home visits, children (mean age 12.1 years; 53.1% girls; 54.4% same-sex sibling pairs) filled out questionnaires about their sibling relationships and their own functioning. Mediation analyses showed no significant direct nor indirect effects of sibling warmth on quality of life, satisfaction with life or PTSS. Significant indirect (but not direct) effects were found for sibling conflict on quality of life and satisfaction with life and on PTSS, through emotion regulation problems. Children experiencing more sibling conflict reported more emotion regulation problems, which were linked to lower quality of life and satisfaction with life and more PTSS. Our study suggests that sibling conflict could be considered a risk factor for child psychosocial functioning in families facing parental cancer. The potentially beneficial effects of sibling warmth were not confirmed by our findings. Limitations and implications of the study and future directions are discussed.