This paper analyses socialization processes in the interaction between two Belgian, Dutch-speaking sisters, aged 10 and 8, more specifically with regard to power dynamics and establishing the roles of socialization target and agent. Socialization is collaborative, but usually entails some division of roles, which is intricately linked to power dynamics. Consequently, socialization efforts, and the socialization roles of target and agent, can be discarded or contested as part of these power dynamics. The analysis shows that socialization efforts between the sisters are often accepted, but also regularly contested and resisted. Moreover, the data indicates that roles and goals of some socialization efforts are so unclear that the boundaries between socialization efforts and interactional actions that aim to gain control become blurred. In conclusion, socialization must not only be considered in terms of its learning potential, but also as a power struggle with intricate and complex negotiation dynamics.