The present study examined several distinct indicators of regulation (i.e., task-based executive function, surveyed child effortful control, and surveyed household chaos) as moderators of longitudinal bidirectional links between developmental changes in harsh parenting (HP) and child externalizing behaviors (EXT) from age 9 to 14 years. The sample included 311 children (50.4% female; 111 White or European American; 97 Hispanic or Latino; 103 Black or African American). We conducted cross-lagged panel analyses and utilized multiple reporters (mother, father, and child). Regarding bidirectionality between HP and EXT, findings were mixed depending on informant, but overall more child effects than parent effects or bidirectional effects emerged. Child and household regulation moderated certain effects, providing initial evidence of the potential role of regulations in bidirectional links between HP and EXT. The present study adds impetus to considering child self-regulation and household chaos as critical features influencing the bidirectional link between parenting and child functioning.