In line with the Matthew-effect in reading, reading comprehension and leisure time reading tend to be reciprocally related. Whereas prior research invested much efforts in the identification and description of variables explaining individual differences in reading comprehension, less efforts were spend on the exploration of variables important for the development of leisure time reading. This study focuses on family literacy activities in preschool age -- joint book reading, joint library visits, and the teaching of letters -- and how these relate to the children' s later leisure time reading and reading comprehension. Furthermore, the role of parents' education is considered. Empirical findings are based on a sample of N = 1.242 children from the National Education Panel Study (NEPS). Joint book reading and joint library visits in families, both aspects of informal literacy activities, predicted leisure time reading of children in Grade 4, which was related to their reading comprehension. In addition, disparities with regard to parents' education were found. The results are discussed against the background of ways to promote children's leisure time reading and practical implications are derived.