Grimes has given birth to her first child.
The 32-year-old Canadian singer welcomed her and Elon Musk's first child together, a baby boy.
Earlier in the day, Elon declared the birth was just "a few hours away", before later adding another tweet to say that "mom and baby [was] all good".
When one fan asked if they had a boy or a girl, Elon confirmed he was the proud father of a son.
"Mom & baby all good," he wrote on Twitter amid a conversation with someone who follows his posts. When asked about the child, he would only say it was a boy. When asked about the name, he wrote "X Æ A-12 Musk."
Elon already has five children from past relationships.
— Elon Musk (@elonmusk) May 5, 2020
Meanwhile, Grimes - who is yet to comment publicly on the news of her arrival - previously confessed that falling pregnant has been a "profound" experience.
She said: "For a girl, it’s sacrificing your body and your freedom. It’s a pretty crazy sacrifice and only half of the population has to do it.
"It was really profound to me when I decided I was going to do it, to actually go through the act of unprotected sex. I’m just like, I have sacrificed my power in this moment. I have, like, capitulated. And I have spent my whole life avoiding that situation. I have never capitulated to anything, so it was just a profound commitment."
— Elon Musk (@elonmusk) May 5, 2020
And whilst her little one was born a boy, Grimes recently said she wants to let her baby choose their own gender identity.
Asked whether she's expecting a boy or a girl, Grimes said during a YouTube live stream: "I don't want to say the gender of the baby ... because I feel like their privacy should be protected. I don't think they can consent to being famous or being in public ... I don't want to gender them in case that's not how they feel in their life. I don't know, I just feel like it doesn't need to be known ... They may decide their fate and identity."