We just got a closer look at Grimes' and Elon Musk's new baby, which they appear to simply be calling 'X'

• Both Grimes and Elon Musk's mother, Maye Musk, posted photos and videos of the couple's new baby over the weekend.
• In a tweet on Saturday, Maye Musk posted a photo of Elon Musk and the baby on a couch, writing, "X, welcome to this world ... You are so adorable."
• Late Sunday night, Grimes shared a video on her Instagram story of Elon Musk holding the baby and rubbing its back.
• The baby's name, X Æ A-12 Musk, has caused confusion over the last week, with many people wondering how it's pronounced. Given Maye Musk's tweet, it appears they're calling the baby "X" for short.
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Tesla and SpaceX CEO Elon Musk and the musician Grimes' new baby turns a week old today, and we just got a closer look at him, thanks to Grimes and Musk's mother, Maye.

"X, welcome to this world ... You are so adorable," Maye Musk tweeted on Saturday. "Congrats ⁦@elonmusk⁩ and ⁦⁩ who will celebrate her first #MothersDay tomorrow." She shared a photo of Elon Musk with the baby, taken by Christiana Musk, who's married to her son, Kimbal.

And late Sunday night, Grimes posted a video to her Instagram Story of Elon Musk holding the baby and patting his back.

Musk and Grimes have said they named the baby X Æ A-12 Musk, and the name has caused confusion over the course of the last week. The couple appears to differ in their pronunciation — Musk said last week on the "Joe Rogan Experience" podcast that the first part of the name is pronounced "X Ash," while Grimes said in an Instagram comment that it's pronounced "X A.I." Musk said "A-12" stands for a type of CIA aircraft, which had the internal codename "Archangel," meaning the name is likely said "X Ash Archangel."

California state law doesn't allow for special characters, numbers, or "inappropriate" hyphenation on birth certificates, so it's unclear what will actually appear on the birth certificate.

Either way, given the wording of Maye Musk's tweet, it appears that they're just calling the baby "X" for short.