The current investigation evaluated whether cognitive processes characteristic of the Social Information Processing model predicted parent-child aggression (PCA) risk independent of personal vulnerabilities and resiliencies. This study utilized a multimethod approach, including analog tasks, with a diverse sample of 203 primiparous expectant mothers and 151 of their partners. Factors considered in this study included PCA approval attitudes, empathy, reactivity, negative child attributions, compliance expectations, and knowledge of non-physical discipline alternatives; additionally, vulnerabilities included psychopathology symptoms, domestic violence victimization, and substance use, whereas resiliencies included perceived social support, partner relationship satisfaction, and coping efficacy. For both mothers and fathers, findings supported the role of greater approval of PCA attitudes, lower empathy, more overreactivity, more negative attributions, and higher compliance expectations in relation to elevated risk of PCA. Moreover, personal vulnerabilities and resiliencies related to PCA risk for mothers; however, fathers and mothers differed on the nature of these relationships with respect to vulnerabilities as well as aspects of empathy and PCA approval attitudes. Findings provide evidence for commonalities in many of the factors investigated between mothers and fathers with some notable distinctions. Results are discussed in terms of how findings could inform prevention programs.