Elon Musk’s Dad Told Him on Father’s Day 2022 That He Fathered Second Child with Former Stepdaughter: Book

According to Musk's upcoming biography by Walter Isaacson, the billionaire found out the news in an email

Elon Musk's new biography sheds light on how he found out that his estranged father, Errol Musk, had fathered a second child with his former stepdaughter, Jana Bezuidenhout.

According to Elon Musk by Walter Isaacson, which hits shelves Tuesday, on Father's Day in 2022, Errol told the 52-year-old billionaire the news in an email.

"The only thing we are on Earth for is to reproduce,” said Errol, who has seven children, per the book. "If I could have another child I would. I can't see any reason not to."

Back in July 2022, Errol, then 76, told The Sun that he and Bezuidenhout had a second child in 2019, two years after the birth of their son, Elliot Rush, in 2017.

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from celebrity news to compelling human interest stories.

In a 2018 interview with the U.K.'s Sunday Times, Errol said he and Bezuidenhout began their relationship while he helped her get over a breakup.

According to the outlet, Bezuidenhout was only 4 years old when Errol married her mother, Heidi. Errol and Heidi were together for 18 years and had two children before their divorce. Years later, Bezuidenhout and Errol would reconnect.

"We were lonely, lost people," he told the Times. "One thing led to another — you can call it God's plan or nature's plan."

Errol said he did not consider Bezuidenhout to be his stepdaughter and claimed she spent most of her time away from the family while growing up.

Related: Inside the Complicated Relationship Between Elon Musk and His Estranged Father, Errol Musk

Last July, court documents revealed Musk welcomed twins with Neuralink executive Shivon Zilis in November 2021. The billionaire seemingly alluded to the baby news on Twitter, now known as X.

"Doing my best to help the underpopulation crisis. A collapsing birth rate is the biggest danger civilization faces by far," he wrote at the time.

In a series of follow-up messages, he added, "I hope you have big families and congrats to those who already do!"

In addition to his two children with Zilis, Musk shares three children with Grimes and is also dad to 18-year-old twins Vivian Jenna Wilson and Griffin, along with triplets Kai, Damian and Sax, who were born in 2006, with his first wife, Justine Wilson. The two had another son, Nevada, who died at 10 weeks.

Related: Elon Musk 'Wants Smart People to Have Kids,' Executive He Welcomed Twins with Says in New Book

Musk previously spoke about his fractured relationship with his father. In an interview with Rolling Stone in 2017, he called Errol a "terrible human being" and said he first experienced a rift with his father when he was a child following his parents' divorce.

With all three of the Musk children staying with their mother after the split, the billionaire said he felt sympathy for his father, who seemed "lonely" and "very sad" by himself.

"Yeah, I was sad for my father," the SpaceX CEO — born in Pretoria, Transvaal, South Africa — told Rolling Stone. "But I didn't really understand at the time what kind of person he was."

He said he moved in with his father and soon realized it "was not a good idea."

"He was such a terrible human being," he said. "You have no idea."

Despite the criticisms, the billionaire also complimented his father's engineering talents and said he inherited his own skills from Errol.

"In my experience, there is nothing you can do," he told Rolling Stone of his attempts to repair their relationship. "Nothing, nothing. I wish. I've tried everything. I tried threats, rewards, intellectual arguments, emotional arguments, everything to try to change my father for the better, and he… no way, it just got worse."

Simon & Schuster's Elon Musk by Walter Isaacson is due out Sept. 12, and is available for pre-order now.

For more People news, make sure to sign up for our newsletter!

Read the original article on People.