(CNN) – Singer Grimes and Tesla and SpaceX CEO Elon Musk have welcomed their second child together, a daughter named Exa Dark Sideræl Musk.
The girl was born via surrogacy last December, Grimes revealed in a wide-ranging interview with Vanity Fair published Thursday.
Although the 33-year-old Canadian musician apparently had no intention of announcing the birth of her second daughter, whom they call “Y,” she shared the news after Vanity Fair reporter Devin Gordon heard a baby cry.
Grimes and Musk previously welcomed a son named X Æ A-Xii, pronounced: “X AI Archangel” or “X,” in May 2020.
Musk, 48, has five other children: twins Griffin and Xavier and triplets Damian, Saxon and Kai, from a previous marriage.
The couple split in September 2021, but Grimes, whose real name is Claire Elise Boucher, described their relationship status as “very fluid”.
“There’s no real word for it,” he told Vanity Fair. “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 stuff, and I don’t expect other people to understand that.”
On Thursday, Grimes told fans that her Vanity Fair cover story was intended to talk about her work, not her personal life. “Def held back a lot, contrary to the starter,” he tweeted. He added: “And it was not her intention to know about my daughter, so please respect her privacy as I would love for her to be able to live as private a life as possible.”
She later clarified their relationship status in a separate tweet, saying that she and Musk had broken up again since the Vanity Fair article was written, but added that Musk is “my best friend and the love of my life, and my life and my art are now forever dedicated to The Mission, I think Devin wrote that part of the story very well.”