Girls In Pants/Forever In Blue by Ann Brashares

Four close friends remain linked by a single pair of mysteriously fitting jeans as they spend summers apart and face pivotal moments in their lives; through romances, family struggles, loss, and choices about the future, each girl confronts grown-up questions about identity and responsibility. The shared garment becomes a symbol of their bond as they weather misunderstandings and hardships, ultimately learning about independence, forgiveness, and the lasting strength of their friendship.

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