Chronic health conditions, such as pediatric cancer, have been associated with a variety of stressors as parents manage multiple hospital and clinic visits, medication adherence challenges, and financial upheaval. Parents may struggle to balance the physical and emotional impact that a prolonged illness can have on the family and other negative adjustment outcomes. The goals of the present study were to further understand psychological caregiver responses to having a child diagnosed with pediatric cancer by examining the relationship of multidimensional components (i.e., factors/subscales) in illness uncertainty to posttraumatic stress, with attention paid to global psychological distress as a possible mediator of this relationship. Studies have documented significant relationships among these constructs in chronic illnesses; to our knowledge no studies have examined all three constructs concomitantly. The most thorough approach to examining these relationships is to examine theoretically meaningful pathways in one simultaneously estimated model. Path analysis is a specific type of Structural Equation Modeling) that allows testing of a causal model consisting of a series of hypotheses regarding the interrelationship of variables studied. Our analyses were driven by one research question; investigating the subcomponents of illness uncertainty and the subsequent relationship to global psychological distress and posttraumatic stress, via two competing models. Hypothesized model one represented the best fit to the data, accounted for 47.30% of the variance in posttraumatic stress symptomatology, and the subcomponent or factor of ambiguity had significant indirect effects on posttraumatic stress symptomatology, as mediated through global psychological distress, as compared to any other of the subcomponents of illness uncertainty (e.g., lack of clarity or unpredictability). The findings in this thesis, particularly those identifying subcomponent symptoms of illness uncertainty on posttraumatic symptomatology and global psychological distress, suggest that further research and greater clinical attention to parents' adjustment to childhood cancer is warranted. Future research could aim to better understand and, ultimately, reduce the array of illness uncertainty factors that might impact the psychological well-being (e.g., increase global psychological distress) in both parents and children from the onset of illness to survivorship, and therefore decrease prevalence rates of posttraumatic stress symptomatology in this unique chronic illness population.