Elon Musk and Grimes attend the Costume Institute Gala at the Metropolitan Museum of Art in May 2018.

  • Tesla CEO Elon Musk and musician Grimes have announced the birth of their first child.
  • The baby boy was born Monday evening.
  • Musk and Grimes, whose real name is Claire Boucher, publicly announced they were dating at the annual Costume Institute Gala at the Metropolitan Museum of Art the first week of May 2018.
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Tesla and SpaceX CEO Elon Musk and musician Grimes have had their first child together.

Musk announced the birth of their child Monday evening on Twitter, saying, "Mom & baby all good." In follow-up tweets, Musk wrote that the couple has a baby boy.

One Twitter user asked Musk the name of their child, to which the tech billionaire responded, "X Æ A-12 Musk."

It's Grimes' first child - Musk has five sons with his first wife, Justine.

Grimes announced she was pregnant in January via a cryptic social media post that showed her with a fetus Photoshopped into her belly. During a livestream on Twitch in February, she said that the baby's due date was May 4th. Musk tweeted that the baby was due on Monday.

The couple's first child together comes almost exactly two years after they made their debut as a couple. In May 2018, Musk and Grimes, whose real name is Claire Boucher, took both the business and music worlds by surprise when they revealed they were dating, walking the red carpet together at that year's Costume Institute Gala at the Metropolitan Museum of Art.

Musk grew up in Pretoria.

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