Borderline personality disorder (BPD) involves disruptions in attachment, self, and self-regulation, domains conceptually similar to developmental tasks of early childhood. Because offspring of mothers with BPD are at elevated risk of developing BPD themselves (White, Gunderson, Zanarini, & Hudson, 2003), studying them may inform precursors to BPD. We sampled 31 children age 4–7 whose mothers have BPD and 31 normative comparisons. We examined relationships between mothers' Adult Attachment Interview (AAI) representations (George, Kaplan, & Main, 1984), mothers' observed parenting, and children's narrative representations. Replicating previous studies, mothers with BPD were more likely to be classified as preoccupied and unresolved on the AAI. In a larger sample, which included the current one, we also replicated two underlying AAI dimensions found in normative samples (Roisman, Fraley, & Belsky, 2007; Whipple, Bernier, & Mageau, 2011). Controlling for current mood, anxiety, and other personality disorders, mothers with BPD were significantly higher than were comparisons on the preoccupied/unresolved, but not the dismissive, dimension. Children's narrative representations relevant to disruptions in attachment (fear of abandonment and role reversal), self (incongruent child and self/fantasy confusion), and self-regulation (destruction of objects) were significantly correlated with the preoccupied/unresolved, but not the dismissive, dimension. Furthermore, mothers' parenting significantly mediated the relationship between the preoccupied/unresolved dimension and their children's narrative representations of fear of abandonment.