Sibling conflict and theory of mind

This study examined conflicts between siblings in an attempt to identify variables that are related to false-belief understanding. The variables investigated were children's use of mental state terms and specific types of arguments (Slomkowski & Dunn, 1992) that occurred during conflict episodes. Twenty-two children between 3 and 5 years of age were administered eight false-belief tasks and were also videotaped while playing with an older sibling. Use of other-oriented arguments by the target child was significantly associated with success on false-belief tasks after controlling for age and general language ability. No use of argument was negatively related to performance on the false-belief tasks after controlling for age and general language ability. Neither the use of self-oriented arguments nor use of mental state terms was found to be associated with false-belief performance. The findings indicate that specific features of sibling conflicts are related to children's developing false-belief understanding.