Congratulations are in order for Elon Musk and Grimes who welcomed their son just yesterday. Elon couldn’t help but share the news with the world as fans pelted him with questions about when his girlfriend First, he tweeted that they were just a few hours away from the birth of their baby, and when he arrived, he added that both Grimes and the baby were happy and healthy.

Grimes Explains Why She & Elon Musk Named Newborn "X Æ A-12 Musk"
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Previously, Grimes told fans that she didn’t want to share the baby’s name because people were having a hard time understanding it, but as soon as the child was born,  Unsurprisingly, the news sparked quite the discussion on social media, so Grimes stepped forward to explain how they came up with their unique name.

“X, the unknown variable,” she wrote. “Æ, my elven spelling of Ai (love &/or Artificial intelligence) A-12 = precursor to SR-17 (our favorite aircraft). No weapons, no defenses, just speed..” She also added, “”A=Archangel, my favorite song.” The internet is debating how to pronounce it, but many are speculating that the child’s name is Ash. Check out Grimes tweeting the details below.