The current study aims to compare positive and negative measures of psychosocial functioning among children with sickle cell disease (SCD) and their healthy siblings. Participants were 41 African-American children with SCD, 97 healthy siblings, and their primary caregivers. Primary caregivers completed self-report questionnaires assessing child behavioral problems, while children with SCD and siblings completed self-report questionnaires assessing coping, self-efficacy, and perceived social support. No significant differences were noted between children with SCD and their siblings on all measures. Both groups reported self-efficacy and perceived social support within the normative range, and endorsed significantly greater use of Positive/Approach coping. In general, both groups of children do not have clinically significant behavioral problems. However, secondary exploratory analyses identified that a greater percentage of children from both groups scored above the established clinical cutoff on the behavioral summary scores. Number of visits to the emergency room was related to behavioral problems in children with SCD. While previous reports have been mixed in their findings that children with SCD are at greater risk for psychosocial and other behavioral problems, the current report finds that children with SCD and their healthy siblings endorse positive psychosocial functioning and as a group do not have clinically significant behavioral problems. Nonetheless, ongoing psychosocial evaluation for children receiving treatment for SCD is vital.