There was some head-scratching last month when tech billionaire Elon Musk and his partner Grimes revealed the name of their son.
When little X Æ A-12 was introduced by his parents to the world, questions were raised about the unusual choice of name.
The couple responded on social media with a breakdown of the name's meaning and there was speculation over how it might be pronounced.
But the couple came up against another hurdle - California law, which dictates that a baby's birth certificate must include a name that uses “the 26 alphabetical letters of the English language."
However, a birth certificate obtained by TMZ appears to confirm news that Grimes and Musk got around this rule by using roman numerals in place of numbers.
Their son's first name is also simply X, making his full name X AE A-XII Musk.
Besides the arrival of his son, his seventh child, Musk has had a busy month with the launch of his SpaceX rocket, initially delayed due to bad weather conditions.
The launch marked the first time NASA had sent astronauts into space from the US since 2011.
“It’s been 18 years working towards this goal. It’s really hard to believe that it’s happened," Musk said following the successful lift-off.
“This is a craft made by humans, for humans, I think it’s something humanity should be proud about occurring on this day."
