Despite growing attention to resilience following childhood maltreatment, it remains unclear how the development of resilience unfolds over time among child welfare-involved adolescents. Further, little is known about the immediate and enduring effects of two important attachments in children’s lives, namely caregiver–child relationship and deviant peer affiliation, on resilience development over time. This study sought to examine the ways in which caregiver–child relationships and deviant peer affiliation shape developmental trajectories of resilience among child welfare-involved youth. Data were drawn from the National Survey of Child and Adolescent Well-Being. Latent growth curve modeling was conducted on a sample of 711 adolescents. The results revealed that adolescents’ resilience increased across a 36-month period since initial contact with Child Protective Services. Better caregiver–child relationships were associated with a higher initial level of resilience among adolescents, whereas higher deviant peer affiliation was associated with a lower initial level of resilience. Significant lagged effects were also found; caregiver–child relationship quality and deviant peer affiliation at baseline were associated with resilience at 18 months after. The findings suggest that interventions that aim to promote positive caregiver–child relationships and prevent deviant peer relationships may help foster resilience among adolescents who have experienced child maltreatment.