Dr. O’Neill heads the Dana-Farber/Boston Children’s pediatric Liver Tumor Center and is Associate Professor, Harvard Medical School (Boston, MA). She chairs the Liver Tumor Committee of the Children’s Oncology Group (COG), a large cooperative network focused on cancers of children and young adults, funded by the National Cancer Institute (NCI). Her contributions to FLC research include leading clinical trials at her home institution and, through COG, over multiple institutions. She collaborated with Dr. John Gordan to develop the “Clinical Guideline for the Diagnosis and Treatment of Fibrolamellar Carcinoma” (Hepatology, 2026).