As the proportion of children born to unmarried parents continues to increase, it is important to understand how these parents navigate the complex roles of jointly raising their child and the potential benefits of keeping unmarried fathers involved in their child’s life. This panel examines the very earliest periods of the parents’ relationship and father involvement (during the prenatal period and at the child’s birth), as well as coparenting and involvement over the child’s young life (through age 9). Importantly, the combined papers explore a wide range of outcomes, including maternal health, paternal harsh parenting, and child behavioral problems. And given that the population of Hispanic children continues to rise (many of whom are children of immigrants), the panel pays close attention to father involvement among immigrant families. The first paper uses data from a new birth cohort study of Texas mothers (N=800) to examine how father involvement during the prenatal period is associated with serious maternal perinatal health complications. The results suggest that the involvement of the father during the prenatal period is a strong predictor of maternal health, even among couples who had very little commitment to their relationship prior to pregnancy or who have poor relationship quality. The second paper examines the effect of the fathers’ early attachment to the child (measured by presence at the child’s birth) on harsh paternal parenting over the course of the child’s early life. Using data from the Fragile Families study, preliminary results suggest that being present at the birth substantially decreases harsh parenting of very young children, but the effects fade as the child ages. The third paper also draws on data from the Fragile Families study to examine the effect of nonresident fathers’ coparenting behaviors on young child behavioral problems, and preliminary results suggest that coparenting is a strong predictor of child aggressive behavior. Father engagement and child support contributions are considered as important mediators in this relationship. The fourth paper examines how the context of nonresident father engagement differs for immigrant families. The Fragile Families study provides the only data that allows for a comprehensive portrait of nonresident father involvement among immigrant families based on nativity status of each parent. Nonresident immigrant fathers likely face similar challenges as other nonresident fathers, but their challenges are also compounded by deportation, migration for work, and other legal challenges. Jointly, the papers will inform policies that aim to: enhance coparenting among unmarried parents, keep fathers’ engaged in their children’s lives, and promote the health and well-being of children and families.