Elon Musk's family tree: Billionaire tech mogul Elon Musk recently welcomed his 4th child with Neuralink executive Shivon Zilis. “Discussed with Elon and, in light of beautiful Arcadia’s birthday, we felt it was better to also just share directly about our wonderful and incredible son Seldon Lycurgus,” Zilis posted on X on Friday. A look at Elon Musk’s family tree …