Elon Musk publicly corrected his girlfriend on Twitter after she made a tiny mistake when explaining their son's name.
Grimes gave birth at the start of the week and the couple later revealed that they'd named their son X Æ A-12.
The name quickly went viral with people from around the world guessing how exactly to pronounce it.
One person on Twitter appeared to guess the pronunciation correctly because Musk liked their tweet. The tweet guessed the name was pronounced, "X Ash Archangel".
Grimes later took to Twitter to explain the name, writing: