Fanny Cäcilia Hensel née Mendelssohn-Bartholdy (1805–1847) is one of the most important figures in German Musical Romanticism, are important primary sources for this era. Fanny was a musical prodigy and composer of over four hundred works. Recent scholarship has brought her significant legacy to the foreground, and her work has now been extensively documented, analyzed, performed, and recorded. Fanny’s emergence as a composer and performer in her own right has resulted in the new appreciation of her close musical collaboration with her younger brother, the famed Felix Mendelssohn-Bartholdy (1809–1847), as illustrated in her letters to him. The siblings evoked the sounds of nature, folklore, and emotion that were the focus of early German Romanticism in a new way: through a universal language, music, and its power to interpret written texts. Their development of the new Romantic musical genre, the Lied ohne Worte (Songs without Words), as a uniquely universal form of non-hierarchical communication enabling mutuality between male and female, achieved the goal of the Early German Romantics’ literary experiments.