Heather Sue Mercer is a member of the influential Mercer family, known for their significant financial contributions to conservative political causes and organizations in the United States. She is the younger sister of Rebekah Mercer and daughter of hedge fund manager Robert Mercer. Like other members of her family, she has been actively involved in various philanthropic and political initiatives, often through family-backed foundations and non-profits. She has served as a trustee for the Mercer Family Foundation and was associated with Reclaim New York, a non-profit co-founded by her sister Rebekah Mercer and Steve Bannon, which aimed to promote government transparency and accountability in New York State. Her activities typically align with the family's broader agenda of supporting conservative and libertarian movements. She is also involved in the Mercer family's philanthropic and political activities.