The Flemish poet Prudens van Duyse (1804–1859) wrote an elegy about his deceased sister, Natalia (1842). He repeatedly rewrote, extended, and reprinted it, so the poem is transmitted in different versions. Van Duyse as well as contemporary reviewers and literary historians considered this poem an absolute highlight of his extensive oeuvre. Prudens van Duyse is considered to be a transition figure in Flemish literature: in several poems and prose texts he unfolded progressive views about literature that can be associated with the work of other romantic writers from Germany, the Netherlands, and France. Van Duyse argues that Flemish literature must be guided by imagination and the individual feelings of the author. This was a new insight in Flanders, because the literature of that time was largely dominated by rules prescribed by the chambers of rhetoric. This chapter examines to what extent the poet in Natalia adhered to the prevailing norms for mourning poetry of the time, or whether he implemented the renewal that he proposed in his own poetic texts.