Recent research and public policy have indicated the need for increasing the physical science workforce through development of interest and engagement with informal and formal science, technology, engineering, and mathematics experiences. This study examines the association of family education and physical scientists' informal experiences in science along with the association of informal family science experiences and early initial interest in science through multiple and logistic regression analyses. Research questions addressed are as follows: Controlling for demographic variables, do physical scientists parents' level of education associate with participation in informal family science experiences? And which informal family science experiences are associated with physical scientists that report an initial personal interest in science by elementary school? These questions are analyzed with survey data from Project Crossover (N = 4,285), a sequential mixed-methods study that examines factors influencing entrance into physical science doctoral programs as well as the transition from graduate students to independent researcher. Results indicate that families with higher parental education are more likely to take part in informal science experiences and therefore more likely to provide positive encouragement for their children to develop an early interest in science. Detailed analyses show that the following family forms of informal science education: occupation, diversions and hobbies, and encouragement are associated with an early initial interest in science by elementary school.