This study examines how tension is transmitted between the marital dyad and the parent-child dyad on a day-to-day basis and explores how stable and changing aspects of the family moderate this process of tension spillover. Mothers and fathers (n = 117 couples) separately completed a short diary questionnaire that included a checklist of common daily stressful experiences on each of 42 consecutive days. Hierarchical generalized linear models showed that both mothers and fathers were more likely to have tense interactions with their children on days when there had been some marital tension the previous day. On days when fathers experienced other stressors, such as work overloads or home demands, they were more than twice as likely to experience tension spillover than on stressfree days. Fathers also reported more spillover when their wives were working full-time. In families with adolescents in the house, mothers had more tension spillover Key Words: conflict, daily diary, emotions, marital relations, parent-child relations, spillover. Family and developmental theorists often highlight the interrelatedness of the wife-husband relationship and the parent-child relationship (Belsky, 1990; Parke & Tinsley, 1987). Indeed, several studies have documented that positive parent-child relations are not easily achieved in the face of marital discord. (For a review, see Erel & Burman, 1995.) One explanation for these findings is that negative emotions in one family relationship are likely to transfer to other family relationships. This type of emotional transmission has been referred to as spillover. Spillover takes place when there is a direct transfer of mood, affect, or behavior from one setting to another (Bolger, DeLongis, Kessler, & Wethington, 1989; Repetti, 1987). Although the concept of spillover often has been used to describe the interplay between family and work settings (Crouter, 1984; Staines, 1980), we address a spillover process that involves the transmission of conflict or tense interaction between two family subsystems, the parent-child dyad and the marital dyad. ANALYSIS OF SPILLOVER AT THE FAMILY LEVEL We focus on spillover at the family level of analysis, and we draw not only on theory developed from observations of family systems, but also from empirical research based on the ecological perspective (e.g., Repetti & Wood, 1997). The ecological perspective (Bronfenbrenner, 1989) posits that stressors and other emotionally arousing events outside the family (e.g., work) and inside the family affect individuals and family relationships through the spillover of tension (Brown & Harris, 1978; Margolin, Christensen, & John, 1996). Children, in their interaction with parents, often are the recipients of spillover (Greenberger, O'Neil, & Nagel, 1995). Stressors from outside and inside the family raise demands for adaptation in parents, which may lead to marital tension. This tension then may lead to negative interactions with children. We specifically examine the spillover of tension from one dyad to another. From this perspective, tensions in a particular family subsystem are stressors that lead to additional problems in another family subsystem. Empirical evidence directly documenting spillover effects, however, is not extensive. In an observational study of mothers and children, Repetti and Wood (1997) report that, on average, mothers experiencing stressful work days are more likely to withdraw (become less responsive) than to display irritation with their children. In an earlier study, Repetti (1994) found a similar pattern of withdrawal for fathers coping with job demands. Although emotional withdrawal is not a neutral family behavior (i.e., withdrawal, if persistent, can have negative consequences), it is generally not as immediately detrimental to the emotional state of others as conflict (Bolger, DeLongis, Kessler, & Schilling, 1989). The probability of parent-to-child spillover most likely varies according to the source and the severity of the stressor, as well as other personal and contextual factors. …