"Ay, Dios mío, spare me." Mamá sighs, but playfulness has come back into her voice. "Just what we need, skirts in the law!"
"It is just what this country needs." Minerva's voice has the steely sureness it gets whenever she talks politics. She has begun talking politics a lot. [. . .] "It's about time we women had a voice in running our country." (1.1.65-65)
Mamá uses synecdoche to refer to women, with a piece of clothing (skirts) filling in for the whole person. Reducing women to a frilly garment just emphasizes how much she disagrees that women should do something crazy like use their brains and study.
It started with Patria wanting to be a nun. Mamá was all for having religion in the family, but Papá did not approve in the least. More than once, he said that Patria as a nun would be a waste of a pretty girl. He only said that once in front of Mamá, but he repeated it often enough to me. (1.2.6)
Papá's reaction to Patria's desire reveals a lot about what he thinks a woman should be doing (and it's not serving the Lord). If becoming a nun is a "waste of a pretty girl," that means there must be a proper use of a pretty girl, and it is probably to do with sex and reproduction… since nuns aren't supposed to get married or have children.
So, when it came time for Patria to go down to Inmaculada Concepción, I asked Papá if I could go along. That way I could chaperone my older sister, who was already a grown-up señorita. (And she had told me all about how girls become señoritas, too.) (1.2.8)
The name of the girls' school is Inmaculada Concepción (Immaculate Conception), which is probably a tongue-in-cheek joke on the part of the author. They're obsessed with growing up, getting their periods, and eventually doin' it—these girls are definitely earthly beings.
Then, a shy, embarrassed look came on her face. She explained that we might very well become young ladies while we were at school this year. She went through a most tangled-up explanation about the how and why, and finished by saying if we should start our complications, we should come see her. This time she didn't ask if there were any questions. (1.2.39)
Poor Sor Milagros obviously doesn't have much training in giving the girls the sex talk. When she talks about "complications" she means starting menstruation. The lack of dialogue or even proper terminology just signals how uncomfortable everyone is with this icky icky body stuff.
When she left, Sinita asked me if I understood what on earth Sor Milagros had been talking about. I looked at her surprised. Here she'd been dressed in black like a grownup young lady, and she didn't know the first thing. Right then, I told Sinita everything I knew about bleeding and having babies between your legs. She was pretty shocked, and beholden. (1.2.41)
Sinita is dressed in black because she is mourning her brother's death. This was a tradition kept only by women, not children, so her mourning clothes make her seem like a mature young lady. That's why Minerva is surprised that this seemingly mature girl has no idea what it means to be a woman, biologically speaking.
I lifted the covers, and for a moment, I couldn't make sense of the dark stains on the bottom sheet. Then I brought up my hand from checking myself. Sure enough, my complications had started. (1.2.82)
On the same night that she learns Trujillo's secret (that he's having everyone killed), Minerva gets her "complications." The term is Sor Milagros' clumsy word for her period. So in one night Minerva has grown up in the sense of hitting puberty and also having her eyes opened to the political reality of her country. "Complications" turns out to have a double meaning.
Papá looked at me a long time before he said, "He's got many of them, all over the island, set up in big, fancy houses. Lina Lovatón is just a sad case, because she really does love him, pobrecita." Right there he took the opportunity to lecture me about why the hens shouldn't wander away from the safety of the barnyard. (1.2.104)
Papá is giving Minerva the cold hard facts. Lina's romance with El Jefe, which seemed like a fairytale to the girls, becomes a cheap, ordinary fling. His lecture is an allegory where hens are girls, and the barnyard is their family or their boarding school.
I felt my breath coming short again. At first, I had thought it was caused by the cotton bandages I had started tying around my chest so my breasts wouldn't grow. I wanted to be sure what had happened to Lina Lovatón would never happen to me. (1.2.107)
Minerva equates growing older and developing breasts with being kidnapped by the president. This is not exactly practical but is understandable; she wants to stop her body from developing so that she won't draw the attention of the rapist dictator.
Minerva explained everything to me in detail and with diagrams as we were coming home on the train. I was not one bit surprised. First, she had already told me about cycles, and second, we do live on a farm, and it's not like the bulls are exactly private about what they do. But still, I don't have to like it. I am hoping a new way will be found by the time I am old enough to be married. (1.3.39)
Poor Mate. As the youngest daughter she has a lot of teachers to keep her up to date on what is to come in her life. Minerva's diagrams explain sex and reproduction, but Mate doesn't really need all that much information because, as a country girl, she's had a front-row seat at mating season.
"I know the clouds have already rained," I said, "but, Papá, why did you do it?"
[…] "Cosas de los hombres," he said. Things a man does. So that was supposed to excuse him, macho that he was!
[…] "Why'd you do what you just did?"
[…] I remembered his own words. "Things a woman does." (2.6.74-76)
"The clouds have already rained" is the English translation of the Spanish expression "Ya llovió mucho desde entonces," which basically means that it's water under the bridge, time has passed, the past can't be changed. Minerva matches her father's essentialist answer explaining his motives, indicating that women are compassionate and forgiving.