The Tesla boss, 51, filed a petition with a Texas court along with 36-year-old Shivon Zilis, asking for permission for the children to have their father's last name and contain their mother's last name as part of their middle name.
The revelation means Musk's total number of children, including two with singer Grimes and five with ex-wife Justine Wilson, is now at nine.
The twins with Ms Zilis were born in November last year, just a few weeks before his second child with Grimes was born via a surrogate.
Ms Zilis is the director of operations and special projects at Neuralink, an artificial intelligence start-up launched by Musk in San Francisco in 2016.
This story is from the July 07, 2022 edition of Evening Standard.
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This story is from the July 07, 2022 edition of Evening Standard.
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