Grimes is a mom of two!

Grimes — who is also mom to 22-month-old son X Æ A-12, whom she also shares with the Tesla founder, 50 — toldVanity Fairthat she and Musk welcomed a daughter in December 2021 via surrogate.

Grimes and Elon Musk.Taylor Hill/Getty

Grimes, Elon Musk

Grimes explained her daughter’s unique name to the outlet, tellingVanity Fairthat Exa refers to a supercomputing term, exaFLOPS, while Dark represents “the unknown.” She explained, “People fear it but truly it’s the absence of photons. Dark matter is the beautiful mystery of our universe.”

Sideræl, the third part of Y’s full name, is pronounced “sigh-deer-ee-el,” according toVanity Fair.Grimes called the word “a more elven” spelling ofsidereal,which she defined as “the true time of the universe, star time, deep space time, not our relative earth time.”

Sideræl has a double meaning, too, as a shoutout to Grimes' favoriteLord of the Ringscharacter, Galadriel, who “chooses to abdicate the ring.”

Grimes and Elon Musk.Jesse Grant/Getty; Pascal Le Segretain/Getty

Grimes, Elon Musk

Grimes toldVanity Fairthat she was “fighting” to name her daughter Odysseus Musk, because “A girl named Odysseus is my dream,” but she and Musk settled on Exa Dark Sideræl instead.

RELATED VIDEO: Grimes Reveals Her 5-Month-Old Son with Elon Musk Is ‘Into Radical Art’: ‘He Just Actually Is’

Despitesplitting upin September 2021 after three years together, Grimes toldVanity Fairthat she and Musk are back together.

“There’s no real word for it,” she said. “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.”

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She added that she and Musk are happy together, telling the outlet, “This is the best it’s ever been. … We just need to be free.”

She told the outlet that they plan to have more children too: “We’ve always wanted at least three or four.”

source: people.com