While the U.S. technically has no royal family, various families have ruled Washington throughout its history. None, however, did it for as long, or with quite as much élan, as the Roosevelt clan.

While the two Roosevelts who actually ruled were male, oftentimes the world’s attention was focused on two of its more outspoken female members—Alice Roosevelt Longworth and Eleanor Roosevelt, who just so happened to spend decades trashing each other in public and private. Their volcanic relationship is the subject of a truly pleasurable new book, Hissing Cousins: The Untold Story of Eleanor Roosevelt and Alice Roosevelt Longworth by Marc Peyser and Timothy Dwyer. The dual biography manages to give the reader what he or she wants—the juicy details of the spat—while simultaneously weaving the much bigger story of these dynamic women’s impact in a time when having an impact as a woman was far from easy.

The two women would go on to lead stunning lives. Eleanor famously redefined the role of First Lady, but beyond that she redefined the role of any woman in politics and the public sphere. Alice pushed and expanded society’s boundaries on what a woman could wear, say, do, and think, while accumulating a nearly unmatchable roster of politicians, thinkers, writers, and artists who sought her company and counsel.