Tesla CEO Elon Musk and Shivon Zilis, a top executive at his brain-chip start-up Neuralink, had twins in November 2021

The news of the twins’ arrival brings Musk’s total count of children to nine

Musk's 18 years old daughter recently moved the court to legally change her name to dissociate herself from Musk

Musk, who posted a tweet on May 24 saying "USA birth rate has been below min sustainable levels for ~50 years" and pinned it to the top of his more than 100 million-follower Twitter account

In April, Musk, and Zilis , filed a petition to change the twins’ names in order to ‘have their father’s last name and contain their mother’s last name as part of their middle name.'”

. Musk and his first wife, Justine, had twins in 2004 before welcoming triplets two years later.

Musk subsequently had two children with musician Claire Boucher, who is better known as Grimes. Their second child was born in December 2021 through a surrogate.

In 2017, she reportedly joined Tesla as a project director. Today, Zilis holds the title of director of operations and special projects for Neuralink, where Musk is a co-CEO.