Parent rating scales are used at increasing rates across disciplines to track child development and determine diagnoses/needs. This study explored relationships among parental stress and the validity of parents' ratings of their child's behaviors. Participants include children who were referred for assessment of behavioral, social-emotional, and development difficulties at a major metropolitan hospital in the United States. Parents completed rating scales regarding their own stress (PSI-4-SF) and child behaviors (BASC-3). Present findings indicate caution is warranted when interpreting parent report data of their child's behavior in the context of significant parenting stress. Relying exclusively on parent-report information to assess young children in clinical setting appears contraindicated. Family/situational factors beyond the individual child are important to assess.