We describe a female toddler with rectal bleeding from extensive colonic polyposis. She has epilepsy from infancy attributed to focal cortical dysplasia. Hepatoblastoma was diagnosed at 13 months of age. Germline testing detected a pathogenic APC (adenomatous polyposis coli gene) variant. We discuss the anecdotal management of an atypical, very early-onset symptomatic Familial adenomatous polyposis (FAP) case, and the clinical utility of genetic confirmation in such cases. We review the genotype-phenotype correlation of the APC mutational spectrum, and the existing evidence supporting the hypothesis that cortical dysplasia is part of the APC-related spectrum.