“It’s expensive to be a girl.”

“It is?”

“Because of the hegemony. Boys make more money than girls.”

Rosie’s expression split the difference between impressed and concerned. “I make more money than Daddy.”

“You do?”

Her parents both nodded.

“But it’s because you do a boy job.”

“Doctor’s not a boy job.” Rosie thought about the lopsided politics of her practice. No one was asking James to make breakfast.

“And you have to spend a lot of money on makeup if you’re a girl and buy lots of shoes and hair stuff.”

“None of that’s a requirement.” Rosie owned four pairs of shoes: winter, summer, exercise, and fancy. “Remember when we said you could bake cakes and play with dolls and have pink things, and that did not make you a girl?”

She remembered.

“Neither does makeup and lots of shoes.”

“Are you…” Penn wasn’t sure how to put it. “You can’t determine your gender identity or your career identity or your anything identity based on what’s going to make you the most money. You shouldn’t not be a girl because you could make more money as a boy.”

“And you shouldn’t stay a girl,” Rosie said, “if you think you are or want to be,” she hesitated, “or could be a boy.”

“And if you want to be a baseball announcer,” Penn added quickly, “then that’s what you’ll be.”

Poppy dug her toes into the carpet. “I said I wanted to be a baseball announcer, but really I want to be a scientist.”

“What kind of scientist?” Rosie tried to sound nonchalant instead of overjoyed.

“I think I want to study fish,” Poppy said shyly, “but a fish scientist is called an ichthyologist. And when we were researching our jobs in the library, I was looking up ichthyologist, and Marnie Alison said ‘icky-ologist’ and everyone laughed, so when we had to tell about our job to the whole class, I said baseball announcer instead, but then Jake was a jerk about it, so now I don’t know what to be.”

Rosie couldn’t decide where to focus first: her daughter’s apparent interest in science, which was thrilling, her familiarity with the word “ichthyology,” which was news, her concern with the hegemony, which warranted further discussion for sure but, it being already past her bedtime, perhaps another night, or the fact that her classmates were bullying her about her career choices and who knew what else. She settled on, “Ichthyologist? Is that like marine biology?”

“Sort of, but better. Marine biologists have to do everyone who lives in the ocean. Ichthyologists get to focus on just fish. Did you know,” here her voice dropped to a conspiratorial whisper even though it was just the three of them, “lots of fish switch genders?”

Her parents had no idea.

“They switch or they’re both. Both at once, or first one then the other. Clown fish all start as boys, but some of them become girls later. Parrot fish are all girls, so then one of them has to become a boy—she changes color and everything—but then if another boy comes along, she might go back to being a girl again. Cuttlefish can split themselves down the middle so all the girls on one side can flirt with his boy half, and all the guys on the other side see his girl half so they don’t feel threatened.”

Her parents’ eyes were wide, their mouths half open and almost, but not quite, smiling, a look she felt she occasioned from them too often. But she was too excited to stop.

“But the best ones are the Hamlet fish. They’re called simultaneous hermaphrodites. That means Hamlet fish are both at once. When two of them get together to … you know … the first one lays eggs like a girl and the second one fertilizes them like a boy, but then, the second one lays eggs like a girl and the first one fertilizes them like a boy. Everyone’s both. They take turns. Isn’t that amazing?”

It was. Rosie knew this moment from raising four other children to this point already, the one where suddenly your kids know more than you do about something they’ve discovered all on their own, something real and important not just cartoons or video games. Amazing was exactly what it was.

“Ichthyologist sounds like a wonderful job,” Rosie said. “Why wouldn’t you write about all of this?”

“I can’t write about any of this. Obviously.” It wasn’t just ichthyology, apparently, about which Poppy knew more than her mother. “Marnie Alison’s already making fun of me, and she doesn’t even know about the transgender fish.”

*

Penn waited until he heard Poppy’s turret door close. “Could be?”

“Could be what?”

“She shouldn’t stay a girl if she could be a boy?”

“That’s not what I meant.”

“What did you mean?”

“Okay,” said Rosie. “That’s what I meant.”

“You think she should change back?”

“She hasn’t changed forward. She hasn’t changed at all.”

“She’s changed completely.”

“Okay. She’s changed some. But some she hasn’t. She’s done nothing yet that can’t be undone. She needs to know she can reverse course if she wants to.”