Father involvement was examined multidimensionally using fathers' and children's reports. A total of 61 fathers and 143 children (intact families and stepfather families) from the Avon Brothers and Sisters Study (ABSS) participated in the current study. Measures of father involvement including engagement in shared activity, monitoring, positivity, and negativity were completed by fathers and children. Agreement between father and child reports of involvement was assessed, involvement was compared between biological fathers and stepfathers, and involvement was predicted statistically using father and child factors (e.g., age, gender). There were modest significant associations between fathers' and children's reports of monitoring of positive events, and father-child positivity. Compared to biological fathers, stepfathers did less monitoring of positive events, and were less positive towards their children. Biological relatedness was a significant predictor of monitoring positive events, monitoring negative events, and positivity. Consistent with previous theoretical and empirical accounts, this study demonstrated that being biologically related to your child influences the level of involvement in fathers. / Master of Science