<p>Most work-family conflict research relies on measures that combine antecedents, processes, and outcomes within the same items, limiting the ability to identify factors that prevent negative work experiences from translating into adverse family-directed behaviors. Drawing on work-family conflict and spillover theories, we adopt a more indirect assessment of strain-based work-to-family conflict by examining the day-level link between emotional job demands and evening irritability toward family members, and (exploratorily) test affective work-related rumination as a process indicator. We further introduce self-reflectivity as a stable, person-level cognitive individual difference variable that should attenuate negative spillover by facilitating recognition and interpretation of work-related strain. We test our hypotheses in a 10-workday diary study with two daily measurement points among working parents (<i>N</i> = 86, <i>n</i> = 528 after-work reports and <i>n</i> = 591–606 evening reports). As expected, day-specific emotional job demands were positively associated with evening irritability toward family members. Additional analyses showed that this association was mediated by higher evening affective work-related rumination and was weaker among individuals higher in self-reflectivity. Target-specific (children vs. significant others) analyses revealed a more nuanced pattern: emotional job demands predicted evening irritability toward significant others regardless of self-reflectivity, whereas emotional job demands were positively directly and indirectly (via affective work-related rumination) related to evening irritability toward children at lower, but not higher, levels of self-reflectivity. We discuss the&#xa0;implications&#xa0;of these results for theorizing about strain-based work-to-family conflict, the role of cognition as a boundary condition, and the value of distinguishing targets within the family domain.</p>