This is a cross-sectional analysis of baseline data from a longitudinal panel study evaluating the impact of a social media campaign supporting the MR+ Stream 2 campaign. The panel design includes baseline and endline survey waves; this paper reports only the baseline wave, collected in January 2026, prior to campaign launch. Caregivers included in the study were surveyed in 16 southern Nigerian states: Abia, Akwa Ibom, Anambra, Bayelsa, Cross River, Delta, Ebonyi, Edo, Ekiti, Enugu, Imo, Lagos, Ogun, Ondo, Osun, and Rivers.