Sara Rosner Bronfman is the daughter of the billionaire former Seagram chairman Edgar Bronfman Sr. Bronfman was a leading funder and a member of the leadership team for the controversial multi-level marketing company and cult NXIVM, as was her sister, Clare Bronfman.

Edgar Miles Bronfman was a Canadian-American businessman. He worked for his family's distilled beverage firm, Seagram, eventually becoming president, treasurer and CEO. As president of the World Jewish Congress, Bronfman is especially remembered for initiating diplomacy with the Soviet Union, which resulted in legitimizing the Hebrew language in the USSR, and contributed to Soviet Jews being legally able to practice their religion, as well as immigrate to Israel.