Final answer:
Susan Ford, daughter of President Gerald Ford, had her high school prom in the East Room of the White House in 1975.
Step-by-step explanation:
In 1975, it was the daughter of President Gerald Ford who had her high school prom hosted in the East Room of the White House. As the daughter of the President, Susan Ford held this unique event while her father was in office. The East Room, known for its historical significance and role in hosting many presidential events, was the setting for an intimate high school celebration, marking it as a rare but memorable use of the White House for a personal family occasion.