Grimes has revealed that she had to change the name of her baby son from X Æ A-12 after the law forbid her and Elon Musk from calling their child a name that was not made up of the 26 letters of the alphabet.
According to California's department of health office of vital records, legally, a person can only be named using a combination of these 26 letters, which meant that registering X Æ A-12's name was virtually impossible.
Grimes shared this video of X Æ A-12 sleeping on Musk:The baby boy, who was born earlier this month, was therefore named something slightly different.
On Sunday night, Grimes, 32, replied to one Instagram follower who asked: "Did you change the baby name because of Californian laws ? What is the baby’s new name?"
She replied: "X Æ A-Xii".
The child's name is thought to be pronounced as "X Ash Archangel", and in response to the slightly altered version of the child's name, one follower chimed: "Nice! Just removed the numbers to conform to California law."
She replied: "Roman numerals. Looks better tbh," before later adding: "One dash is allowed."
Explaining the meaning behind her and Musk's unusual baby name, Grimes tweeted: "X, the unknown variable. 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. Great in battle, but non-violent."
The second A in the child's name stands for Archangel, which is Grimes' favorite song, and 12 is a reference to the Chinese zodiac and the year of the rat, with 2020 being believed to be the year of the Metal Rat.
Musk and Grimes have been in a relationship for over two years. They first publically stepped outside as a couple at the 2018 Met Gala, and Musk recently explained his relationship with Grimes with the help of Kylie Jenner.
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