Grimes and Elon Musk had a secret baby and that baby certainly has quite the name

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Vanity Fair published a wide-ranging profile of Grimes on Thursday for the magazine’s April issue, and is it quite the read. Among the many revelations found in the piece: She and Elon Musk are still very much together, sort of — despite reports that the billionaire had since moved on with Australian actress Natasha Bassett. And also, as a very big by-the-way: They secretly welcomed a baby girl into the world late last year.

The couple used a surrogate for the birth of their second child after Grimes had experienced complications when she was pregnant with their two-year-old son X Æ A-12 (or, “X” for short), which was why they were able to keep the news under wraps. And they had still intended to keep their daughter a secret, save for the fact that the journalist who had been invited to Grimes’ home to interview her literally heard the newborn crying from the other room.

And as you might expect, given what they named their son, their daughter also has quite the unconventional name: Exa Dark Sideræl Musk, or as Grimes helpfully explains, “Y” for short. Brace yourself:

Exa is a reference to the supercomputing term exaFLOPS (the ability to perform 1 quintillion floating-point operations per second). Dark, meanwhile, is “the unknown. People fear it but truly it’s the absence of photons. Dark matter is the beautiful mystery of our universe.” She texts me a voice memo with the pronunciation of Sideræl—“sigh-deer-ee-el”—which she calls “a more elven” spelling of sidereal, “the true time of the universe, star time, deep space time, not our relative earth time.” It’s also a nod to her favorite Lord of the Rings character, the powerful Galadriel, who “chooses to abdicate the ring.”

But just so we know that she knows, Grimes is indeed aware that the name is, shall we say, not great.

Grimes is prepared for Y to dislike her name or get tired of it—Grimes got tired of Claire a long time ago—and if she ever decides to change it, her mother will be first in line to help her choose a new one. She’s already got dozens of ideas. She might even change it herself before this article comes out. In addition to Y, she and Musk occasionally call her Sailor Mars, a nod to the Sailor Moon manga series. Exa Dark Sideræl was actually something of a compromise, and she worries it’s a little boring.

“I was fighting for Odysseus Musk,” she writes. “A girl named Odysseus is my dream.”

The 33-year-old also provided some insight into her and Musk’s likewise unconventional relationship, which includes separate living arrangements — as the South Africa native very reasonably doesn’t care for “things to be messy and anime.”

“There’s no real word for it,” she begins. “I would probably refer to him as my boyfriend, but we’re very fluid. We live in separate houses. We’re best friends. We see each other all the time…. We just have our own thing going on, and I don’t expect other people to understand it.” What matters, I offer, is that they’re happy. So are they? “Yeah,” she says. “This is the best it’s ever been…. We just need to be free.” They plan to have more children too. “We’ve always wanted at least three or four.”

Grimes realizes that her kids aren’t going to have a normal upbringing, but they’re preparing them as best they can, with a parenting philosophy that can only be described as questionably eccentric. “The best situation here,” she explained, “is me training the girl and [Elon] training the boy.”

We wish our most sincere congrats and best wishes to the new parents, now that we know.