Brahms's familiar "Wiegenlied" op. 49, no. 4 (1868) is emblematic of numerous nineteenth-century compositions that sonorously enact idealized images of the mother and child. Its back and forth harmonic movement imitates the phenomenal sensation of rocking, and its interlocking syncopations support and interact with the emotive declamation of the singer's voice. Because its musical features are so easily accessible, the "Wiegenlied" has escaped music-analytical attention, its deceptive simplicity seemingly transparent to our music-theoretical gaze. Yet, certain aspects of this music render our familiar analytical or critical strategies inadequate for explaining the intuitions we have about it, aspects that suggest tracing their connections within a broader cultural and musical context. My discussion of the lullaby draws from a number of cultural theorists--among them Friedrich Kittler, Michel Chion, Gilles DeLeuze, Flix Guattari, and Theodor W. Adorno--to theorize the power of the mother's voice (la voix maternelle) in forming lifelong vocal and musical connections. I provide a close reading of Alexander Baumann's "S'is Anderscht" (1842), the Austrian vocal duet that inspired Brahms's composition of the lullaby, and a critical comparison of it with the lullaby. Finally, after uncovering latent etymological sources of several key words in the lullaby's text, I offer a hermeneutic re-reading of the poem, one that ultimately undermines our casual assumptions of this simple childhood song.