Final answer:
In Lois Lowry's novel 'Number the Stars,' Annemarie is glad when she returns to bed after Peter's visit because she knows that her best friend Ellen is safe within her home.
Step-by-step explanation:
The question is referencing the novel Number the Stars by Lois Lowry. In this particular scene, Annemarie Johansen, the main character, is relieved after the visit by Peter, a Resistance fighter. The detail that makes Annemarie glad as she returns to bed after Peter's visit is the fact that her best friend, Ellen, is safe within her home. Despite the dangerous times they are living in, with the Nazi occupation of Denmark, having Ellen safe and sound brings Annemarie a sense of comfort and relief.
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