This study examines the relationship of parent's and children's affective states on in-store family purchase decisions. In particular, the study is interested in determining whether the affective state is related to the interaction strategy selected and their actual role in the decision. The implementation of this study using observational methodology within the store environment makes this contribution valuable and unique. Further, a major contribution of this study is the demonstration that the child's prepurchase affective state is a salient antecedent topurchase decisions of the parent-child dyad. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]