- A new biography of Elon Musk says he has a third child with Grimes named Techno Mechanicus.
- Musk and Grimes had previously tried to keep the existence of their third child private.
A new biography of Elon Musk said the Tesla CEO had a previously unreported third child with the Canadian musician Grimes, his ex-partner. The couple deliberately kept the child's existence private, the book says.
The child, who was born in mid-June 2022 — during the week of Father's Day — is named Techno Mechanicus. He goes by the nickname Tau, after the Greek letter for the number equal to two times pi, which is roughly 6.28. This, in turn, reflects Musk's own birthday — June 28.
The journalist Walter Isaacson was given unprecedented access to Musk over the last two years. Techno's birth was first revealed in a New York Times review of the biography, which is simply titled "Elon Musk."
Accounting for Techno Mechanicus, Musk now has 10 known living children with three different women.
Musk and Grimes, born Claire Boucher, first announced their relationship in May 2018. Since then, the couple announced the birth of two children. Their first was born in 2020 and named X Æ A-Xii, or X. The couple revealed news of his little sister, Exa Dark Sideræl Musk, who goes by Y, in March 2022.
Musk and Grimes have since split, but the musician has previously said their relationship is "fluid."
"Tau is so amazing," Grimes told Isaacson. "He came out with eyes that could just see so deeply into your soul, with so much knowledge. He looks like a little Spock. He's definitely a Vulcan."
Isaacson interviewed Musk's former wives, Justine Musk and Talulah Riley, for the book. He also interviewed Shivon Zilis, the Neuralink manager with whom Musk had two children.
Isaacson's biography has also garnered attention for the scoop that the SpaceX CEO interfered with a Ukrainian offensive attack in Crimea by disabling nearby Starlink coverage.
Musk later tweeted that he never turned the satellites off, saying instead that the satellites were never on and that he refused to activate them. Musk said he feared the planned attack would trigger a nuclear response from Russia.