Why does Gretel not join the league of young girls Boy in striped pajamas?

In "The Boy in the Striped Pajamas," Gretel does not join the League of Young Girls because she is initially more focused on her own interests and the influence of her family, particularly her mother and the Nazi ideology surrounding her. As the story progresses, she becomes increasingly disillusioned with her surroundings and the oppressive nature of her environment. Her character represents the struggle between innocence and the pressures of conformity, making her hesitant to fully engage with the expectations placed upon her.