A mother's mental illness may have a profound effect on her child's development, including an increased risk of the child developing the same disorder. From a developmental psychopathology perspective, offspring provide an opportunity to examine pathways to disorder versus resilience. Borderline personality disorder (BPD) is a severe disorder diagnosed in early adulthood involving stormy relationships, an unstable sense of identity, and self-destructive behavior. Interestingly, the domains of dysfunction are conceptually similar to developmental tasks in early childhood reworked in adolescence: attachment, self development, and self-regulation. Early deviation may increase the risk for later disorder. There are five empirical studies of children whose mothers have BPD, two conducted from a developmental perspective. This article proposes a theoretical framework and an innovative methodology with which to extend this research, and suggests an intervention to bring development back on track if necessary.