As Wordsworth’s biography demonstrates, he was exceptionally close with his younger sister Dorothy, who was instrumental to his identity and creative process. Often, Wordsworth used language and images from his sister’s journals. In “I Wandered Lonely as a Cloud,” the famous image of the daffodils first appeared in one of Dorothy’s journal entries. Dorothy felt a strong attachment to Wordsworth. The Dorothy Wordsworth scholar Frances Wilson presents the relationship as excessive and unhealthy. The article, “Sister Act, a New Take on Dorothy Wordsworth” (NPR, March 22, 2009), covers Wilson’s thesis and features a journal entry as evidence. Dorothy wrote the entry on her brother’s wedding day. She writes, “I kept myself as quiet as I could, but when I saw the two men coming up the walk coming to tell me it was over, I could bear it no longer and threw myself on the bed, where I lay in stillness, neither hearing, nor seeing anything.” The intense diction matches Wordsworth’s feverish presentation of the girl in “A Slumber Did My Spirit Seal.” She, too, “neither hears nor sees” (Line 6). As with the girl, the wedding makes Dorothy experience an ending and traumatic change.

Moreover, Romanticism’s interest in transcending rigid boundaries between life and death resonates with the poem’s blurring of human and nonhuman identity. The possibility that Lucy symbolizes Dorothy underscores how Romantic poetry often challenged conventional categories of identity, imagining more fluid connections between self and nature.

The uncommon bond between Dorothy and Wordsworth has led to speculation that Lucy is Dorothy. Wordsworth uses Lucy to express his many emotions about Dorothy. Dorothy had debilitating migraines, and Coleridge felt that Wordsworth wrote “A Slumber Did My Spirit Seal” to prepare himself for Dorothy’s death. In Coleridge’s view, the poem is a preemptive coping strategy. Yet the migraines weren’t fatal, and Wordsworth died before Dorothy. More generally, the reading of Lucy as Dorothy reflects the importance of Dorothy. The girl dominates the speaker’s mind, and Dorothy consumed Wordsworth; she was his muse, just as Lucy inspired the speakers of the five poems.