The social aspects of co-present phone use have increasingly attracted scholarly attention due to their potential impacts on interpersonal relationships. As a result, this study focused on two instances of socialized co-present phone use, namely shared phone use (ShPU) and social-intended solitary phone use (SISPU). Utilizing a dyadic approach, we examined the association between ShPU (and SISPU) and relationship satisfaction among 823 parent-child dyads (children: Mage = 15.33 years; parents: Mage = 42.74 years). Our study also investigated the indirect roles of self-disclosure and responsiveness in this association. The findings revealed a positive correlation between ShPU and SISPU and parent-child relationship satisfaction. Self-disclosure and responsiveness were found to be significant indirect pathways in this association. Additionally, the study identified specific effects of actor and partner within parent-child dyads. The practical implications of these findings included their potential to promote family harmony and improve parent-child relationships.