Original definitions of psychopathy suggest the existence of two variants that present with distinct clinical features among antisocial adults, but whether these clinical differences originate early in life or emerge at some point during childhood remains uncertain. We examined if primary and secondary variants follow distinct developmental trajectories of theoretically relevant clinical features among children with conduct problems (CP). Participants were 370 children (40.3% girls) with CP initially aged 8.49 years old in average (s.d. = 0.93). Variants indicators (callous-unemotional [CU] traits and anxiety [ANX]) and clinical features were measured at six yearly assessments. A dual trajectory modelling approach was used to identify groups and group memberships were entered in conditional growth models predicting trajectories of clinical features. Four groups were identified: CP-only, anxious (CP + ANX), primary (CP + CU), and secondary (CP + CU + ANX). Both variants showed higher initial levels of impairment than the CP-only group on most features. Compared to the primary variant, membership to the secondary variant was associated with more stable patterns of CP, oppositional problems, narcissism-grandiosity and impulsivity-irresponsibility traits. Moreover, children from the secondary variant showed higher initial levels of impairment in terms of cognitive abilities, depression, victimization, and dependency to teachers, with non-significant effects on the slope parameters suggesting that these early differences persist across development. In addition to showing distinct clinical features relatively early in childhood, children from the secondary variant of psychopathic traits are at high risk of experiencing an increasing psychopathological burden across childhood. The early identification and treatment of these children therefore appears particularly important.