Grimes’ baby names just keep getting more unique.

In a recent Twitter reply, the Canadian musician revealed that her 1-year-old daughter’s name is now a question, almost literally.

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The artist welcomed her second child with Elon Musk back in December 2021, announcing the baby’s name was Exa Dark Sideræl Musk.

But in an interview with Vanity Fair at the time, she said that they actually refer to their daughter by the nickname “Y”.

In the reply to a user on Twitter last week, Grimes explained that she also calls Y by the nicknames “Why?” or “?”, adding, “But the government won’t recognize that.”

Of course, Grimes and Musk are no stranger to picking baby names that can’t quite get approved by the government.

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When their first child, a son, was born in May 2020, the couple announced he would be named X Æ A-12.

But as it turned out, the government of California doesn’t allow numeric digits or special characters in name, so they changed the spelling to X Æ A-Xii

That said, Grimes and Musk have explained that they refer to their 2-year-old son by the nickname X.