In Sophie Kinsella's book "Can You Keep a Secret?", a character expresses concern over Emma's situation, highlighting her vulnerability. The comparison to going into battle while wearing a nightgown underscores the seriousness of her predicament, emphasizing that she is ill-prepared for the challenges ahead. This metaphor illustrates the sense of danger and the need for adequate protection in a challenging environment.

The quote conveys the character's frustration and desperation, signaling that Emma's lack of readiness could lead to disastrous consequences. It encapsulates a theme of vulnerability and the importance of being prepared to face life's battles, both literally and metaphorically. In this context, the phrase serves as both an apology and a warning, reflecting the book's exploration of personal challenges and unexpected situations.