Billionaire entrepreneur, Elon Musk and musician Grimes recently revealed having a secret third child together. The revelation came to light through Musk's forthcoming biography mentioning their third child named Techno Mechanicus. Affectionately known as “Tau,” this new addition brings their brood to a total of three.

Not much information is available about this new addition, including the birth date. Musk, aged 52, and Grimes, aged 35, already have two other children: a 1-year-old daughter named Exa Dark Sideræl (nicknamed “Y”) and a 3-year-old son named X Æ A-12.

Musk and Grimes' relationship first became public in May 2018.

Their first child, X, was born in May 2020, followed by Exa Dark Sideræl in December 2021.

However, the couple separated just a few months after their daughter's birth. It remains uncertain if they have since reconciled at the time.

Now, it's not just Elon Musk's biography that revealed ‘Tau.” Grimes also recently tweeted a request to Musk to see her son. She expressed her frustration about not being allowed to see a photo of her children until that moment.

There's no public disclosure regarding whether Elon Musk and Grimes have had private discussions, especially after welcoming third child.

Musk has had previous relationships with different mothers for his 11 children. He had a child during marriage to Justine Wilson, but unfortunately passed away at 10 weeks old due to SID. They later welcomed twins, Griffin and Vivian, in 2004, followed by triplets Kai, Saxon, and Damian in January 2006, before their divorce.

Elon Musk and Grimes' secret third child wasn't his first. Musk also had secret twins with Shivon Zilis, Neuralink's director of operations and special projects, in November 2021. Just before Grimes gave birth to their second child.