There are various sport pathways that athletes follow in their sport participation journey. The Developmental Model of Sport Participation (DMSP; Fraser-Thomas & Côté, 2016) suggests an athlete's journey starts one of two ways: sampling (often referred to as early diversification), or specializing. While research into the cost of early specialization is growing, little attention has focused on how family members' (i.e., parents, siblings) demographic and sport participation patterns may influence whether athletes specialize or diversify during early development. The purpose of this study was to examine potential differences between early specializers and early diversifiers in terms of sport participation and level of education of mothers and fathers, as well as sport participation and birth order of siblings. Athletes (N=483) of various sports and skill level completed the Developmental History of Athletes Questionnaire (DHAQ; Hopwood, 2013). A k-means cluster analysis was used to determine group membership (i.e., early specializer or early diversifier). Subsequent analysis noted a significant difference between early specializers and diversifiers when comparing fathers' competitive sport participation frequency, fathers' regular physical fitness activities and fathers' regular competitive sport participation. Early specializers had fathers who participated more often in competitive sport, participated regularly in competitive sport and participated regularly in physical fitness activities, whereas early diversifiers did not. No other family differences were found. The possible paternal influence on a child's sport journey will be discussed and future research directions considered.