Wilting violets the Mirabal sisters are not. The protagonists of In the Time of the Butterflies are an all-female super-heroine band. But just because they're incredible justice fighters doesn't mean they don't come up against societal norms about what it means to be a "lady."
The girls grow up in a nice home and are expected to marry well; they are sent to a convent school and all four of them do, indeed, marry as they're supposed to. But they break out of the private sphere that their mother knew as her only realm, and enter into politics and revolutionary militancy. They challenge expectations of femininity without rejecting their womanhood.
Questions About Women and Femininity
Who determines how the girls should behave when they are young?
What is expected of each sister as a young woman?
Whenever Minerva asks for support of her dream to attend law school she is denied. What does that say about women's place in society?
If the women had remained in their home, would they have survived the regime?
Chew on This
The girls' true crime (in the eyes of Trujillo) is stepping outside of the feminine sphere and trying to act in the political realm.
The sisters still adhere to societal rules about women by getting married and having children.