The emotional cascade model proposes that the emotional instability and engagement in maladaptive behaviors within borderline personality disorder (BPD) may be linked to rumination. Previous research has established that BPD is highly related to neuroticism, childhood emotional vulnerability, and parental invalidation. Therefore, the purpose of the current study was to assess whether the constructs of the emotional cascade model relate to other constructs within the BPD nomological network. More specifically, neuroticism, childhood emotional vulnerability, and parental invalidation should relate to the ruminative process and engagement in maladaptive behaviors as described by the emotional cascade model. The current study investigated the relation between these factors using a cross-lagged panel design with data collected online at 3 time points in a student sample and an Amazon Mechanical Turk sample. Neuroticism predicted rumination 1 month later across both samples and for 3 measures of rumination. Childhood emotional vulnerability and parental invalidation predicted rumination 2 months later for 2 measures of rumination in the student sample only. Future studies should continue to investigate the potential role of personality traits and BPD vulnerability factors within the emotional cascade model. (PsycINFO Database Record (c) 2019 APA, all rights reserved).