Question: What is the date of death of Mark Rockefeller's mother?
Sentence (from "Happy Rockefeller"): Margaretta Large "Happy" Rockefeller ("née" Fitler, formerly Murphy; June 9, 1926 – May 19, 2015) was a philanthropist and the second wife of the 49th governor of New York and 41st vice president of the United States, Nelson Aldrich Rockefeller (1908–1979).
Relevant evidence: Yes