Elon Musk wants big families. His own is complicated

Austin, Texas: On a quiet, leafy street of multimillion-dollar properties, one stands out: a 14,400-square-foot mansion that looks like a villa plucked from the hills of Tuscany in Italy and transplanted to Austin, Texas.

This is where Elon Musk, 53, the world's richest man and perhaps the most important campaign backer of former President Donald Trump, has been trying to establish the cornerstone of an unusual family compound, according to four people familiar with his plans.

Musk has told people close to him in recent months that he envisions his children (of which there are at least 11) and two of their three mothers occupying adjoining properties. That way, his younger children could be a part of one another's lives, and Musk could schedule time among them.

Directly behind the villa is a six-bedroom mansion that Musk helped purchase, according to two of the people and public records. The total cost of both properties was about $35 million. When in Austin, he often stays at a third mansion about a 10-minute walk away, the people said.

Three mansions, three mothers, 11 children and one secretive, multibillionaire father who obsesses about declining birthrates when he isn't overseeing one of his six companies: It is an unconventional family situation, and one that Musk seems to want to make even bigger.

A proponent of in vitro fertilization, Musk believes strongly in increasing the world's population. He has even offered his own sperm to friends and acquaintances, including former independent vice presidential candidate Nicole Shanahan, according to two people familiar with his offer. Shanahan turned him down.

Musk has tried to keep his own growing family a secret. The compound, and his efforts to fill it with his children, which have not been previously reported, isn't just a personal matter for him; it is rooted in the existential anxieties that underpin his business empire.

He was an early investor in his electric car company, Tesla, out of concerns about reliance on fossil fuels. He founded his rocket company, SpaceX, now a significant government contractor, so that he could colonize Mars for humans in case Earth becomes uninhabitable.

Over the past two years, he has become increasingly fixated on what he sees as another threat: declining birthrates. He believes a global population collapse is coming that will wipe out humanity. His apocalyptic vision is unlikely, according to demographers, but on X, the social media company he owns, he has been encouraging followers to have as many children as possible.

"It should be considered a national emergency to have kids," Musk posted in June.

Musk spent time temporarily encamped in Pennsylvania, immersed in the presidential campaign and spending tens of millions of dollars to finance Trump's get-out-the-vote operations. Trump's victory could make Musk perhaps the most powerful private citizen in the country, and Trump has already said he would appoint the billionaire to oversee an "efficiency commission" to scrutinize the workings of the entire federal government.

But it is in Texas where Musk has moved much of his business operations and is trying to establish his family compound. The compound is off to a bumpy start.

One of the mothers, Shivon Zilis, an executive at Neuralink, Musk's brain technology startup, has moved into one of the homes with her children. But Claire Boucher, the musician better known as Grimes, who is the mother to three of his children, is in a protracted legal fight with Musk and has so far steered clear.

The third mother is Musk's first wife, Justine Musk, with whom he has five living children, all in their late teens or older. There is room in the Austin compound if they were to visit, though he is estranged from at least one of those children.

In choosing Sen. JD Vance, R-Ohio, as his running mate, Trump brought declining birthrates to the forefront of this year's presidential election. Vance, who has raised alarms about the issue, made headlines for scolding "childless cat ladies." Musk's push for procreation also aligns globally with world leaders like Prime Minister Giorgia Meloni of Italy and Prime Minister Viktor Orban of Hungary and has made him something of a hero among pronatalists, who believe people should have as many children as possible.

In a biography published in 2015, Musk worried that educated people weren't having enough children. "I'm not saying like only smart people should have kids. I'm just saying that smart people should have kids as well," he said. "I notice that a lot of really smart women have zero or one kid. You're like, 'Wow, that's probably not good.'"

His views seem to echo those of his father, Errol Musk. The elder Musk, who is 78 and has seven children with three women, praised his son's "good genes" and desire to have many children.

"You breed horses," Errol Musk said in an interview in September. "People are the same. If you have a good father and a good mother, you'll have exceptional children. If you have no children, I feel very sorry for you."

In a book published in 2023, Elon Musk told his biographer that he and his father, who lives in South Africa, are sometimes estranged, partly because Errol Musk had two children with his own former stepdaughter. But the elder Musk said that he and his son were in frequent contact and that he had recently traveled to Texas to visit him and his children.

"I haven't met one or two of them because they're still secret," the elder Musk said.

Musk, his attorney and the head of his family office did not return requests for comment. Representatives for Boucher did not return requests for comment. Zilis and Shanahan also did not return requests for comment.

In an interview published Oct. 30, Musk told The New York Post, "I don't own, nor am I building a compound in Austin." Musk, who said he hadn't read The New York Times story, also denied offering his sperm to friends and acquaintances, including Nicole Shanahan, the former running mate of Robert F. Kennedy Jr.

All Musk's Children

Elon Musk and his first wife, Justine Musk, had their first child, a boy named Nevada, in 2002, two years after they married. The child died unexpectedly in infancy.

"Elon made it clear that he did not want to talk about Nevada's death," Justine Musk wrote in a 2010 essay. "I didn't understand this, just as he didn't understand why I grieved openly." Justine Musk wrote that she coped by "making my first visit to an IVF clinic less than two months later."

The couple had five children using IVF before they divorced in 2008: twins, Griffin and Vivian, who are now 20, followed by triplets, Saxon, Damian and Kai, now in their late teens. Elon Musk has said that IVF is a more efficient way of having children because it allows parents to control parts of the process, according to a person who understands his thinking.

By 2016, as the head of Tesla and SpaceX, Musk had amassed a net worth of more than $11 billion, according to Forbes. That year, he warned for the first time on Twitter, the social network now known as X, that the world could be headed for population collapse.

"Consequences of population implosion greatly underestimated," he wrote in response to an article about falling birthrates. In private, he had warned of the issue to his friends and family for years.

He twice married and divorced actress Talulah Riley, whose desire to focus on her career instead of having children was a factor in their breakup, according to three people familiar with her thinking. Representatives for Riley didn't return requests for comment.

In 2020, Musk and Boucher, whom he started dating two years earlier, had their first child, a son they named X Æ A-Xii, or X for short.

He started becoming even more vocal about the declining population. "Population collapse is 2nd biggest danger to civilization after AI," he tweeted in July 2020, a couple of months after X's birth.

Over the next few years, Musk had more children with Boucher as well as with Zilis.

The arrangement created tensions that sometimes flared on social media.

In 2021, without Boucher's knowledge, Musk donated sperm to Zilis, who became pregnant with twins through IVF, according to three people familiar with the couple. That same year, the billionaire and Boucher were expecting a second child also conceived via IVF but carried by a surrogate.

The two women, who had been friends and ran in similar social circles, had unknowingly been at the same Austin hospital around the same time, according to an authorized biography of Musk by Walter Isaacson. Zilis had twins in late 2021, weeks before Boucher's child, a girl, was born. Boucher found out that Musk had fathered Zilis' children a month after they were born, according to two people close to the situation.

Further complicating matters, Musk took a name that he and Boucher had chosen for their daughter -- Valkyrie -- and gave it to one of Zilis' twins, according to two people familiar with the naming. Boucher was so offended that she wrote a song about the episode, which she posted to Twitter.

"A girl cursed with my daughter's name," Boucher wrote in a now-deleted tweet, "will now carry her mother's shame." (In the end, Zilis changed her daughter's name, while Boucher chose a different name for her child.)

By then, Boucher was living in Austin and co-parenting her children with Musk. Zilis was also living in the city, according to three people close to her.

Both women, at times, have treated Musk as their romantic partner, and backed his beliefs about a population crisis and having children to save humanity.

"I've spent most of my adult life working on what I figured would most contribute to a better future within the aperture of my skill set, but having kids makes it non-negotiably and viscerally obligatory to fight for that goal," Zilis posted on X in March.

Fear of a Depopulated Planet

Over the past three years, Musk has ratcheted up his alarm over the declining birthrate across the United States and elsewhere. In 2021, his foundation gave $10 million to the University of Texas to study fertility and population trends. He has posted at least 67 times on the subject since 2021, 33 of them in the last year.

"I'm doing my best to encourage more people to become parents and ideally have three or more kids, so humanity can grow," he posted in February.

Musk has been celebrated by supporters of the growing pronatalist movement. While pronatalists on the Christian right believe children should be conceived through traditional marriages between a man and a woman, Silicon Valley adherents accept a wide array of family structures as well as reproductive technology like IVF.

Simone and Malcolm Collins, who founded the Pronatalist Foundation in 2021, have come to the movement from worry about demographic collapse and applaud what Simone Collins called Silicon Valley's "thinking about the future in a clearer way." A married couple with four children, they said they were working for the betterment of humankind.

"Our worldview value is based around the goal of an eventual pluralistic intergalactic human civilization," Malcolm Collins said.

Few demographers believe the planet will face a catastrophic demographic event in the next few decades. The United Nations said in July that the global population, which is now 8 billion, is expected to grow by 2 billion over the next 60 years, and then gradually fall by about 700 million people.

Nonetheless, a number of developed countries like Japan, Italy and Germany have been struggling to increase population as they face the economic consequences of a declining birthrate, like a shrinking workforce and the costs of caring for the elderly.

"There is an awful morality to those who deliberately have no kids: they are effectively demanding that other people's kids take care of them in their old age," Musk posted on X in 2023, in response to a video of dual-income couples bragging about having no children.

These trends have alarmed other global tech figures. Skype co-founder and Estonian billionaire Jaan Tallinn has donated hundreds of thousands of dollars to the Collinses' foundation and is himself a father of five. The founder of the messaging app Telegram, Pavel Durov, claimed in July that he had fathered more than 100 biological children through sperm donation. Durov, who is under arrest in France over charges of allowing criminal activity on Telegram, has said he plans to "open source" his DNA.

Musk has offered to share his DNA. At a dinner party held at the home of a well-known Silicon Valley executive last year, Musk offered to provide his sperm to a married couple he had met socially only a handful of times, according to two people who were present for the interaction.

The couple had mentioned at the dinner that they were having trouble conceiving a child. Musk told them he was happy to assist, and boasted about his many children, according to the people present.

In the winter of 2022, Musk made a similar suggestion to Shanahan around the time that Shanahan told people she had sex with Musk. (Shanahan has denied that she had an affair with Musk.)

Shanahan has a daughter with her former husband, Google co-founder Sergey Brin. She declined Musk's offer.

The Compound

Initially, Musk had hoped to build a compound for his families on hundreds of acres that he and his companies owned outside Austin, near Tesla's headquarters, according to four people familiar with the plans. But that idea appeared to fall apart after the Justice Department began investigating whether Tesla's resources had been used on a secret effort to build a glass house for Musk's personal use, according to The Wall Street Journal.

In August 2023, Musk said he was "not building a house of any kind," in a post on X.

By that time, Musk had begun touring Austin for homes that could fit his growing families but was having trouble with at least one of the mothers of his children.

He had been living with Boucher in a 6,900-square-foot house on a small cul-de-sac, according to three people familiar with the couple, when the pair welcomed a third child, a son born via surrogate.

Musk wanted to buy property next to the one he lived in with Boucher so that he could create a private compound and incorporate more of his children.

But Boucher, who once described her relationship with Musk as "very fluid," moved out in the summer of 2023. She eventually left Austin amid a custody battle with Musk, according to three people familiar with her move.

Still Musk continued his home purchase spree. He offered some homeowners 20% to 70% above the value of their houses, according to those homeowners. Some were required to sign nondisclosure agreements just to see the offer, according to three people familiar with the agreements.

It's unclear which members of Musk's families will live in those homes. Some of his oldest children aren't close to their father, including his daughter Vivian, who is transgender. In an interview, Musk said Vivian was "dead, killed by the woke mind virus." Vivian, for her part, accused Musk of pretending to care about his children. "You are not a family man," she wrote on Threads in August. She declined to comment.

Only Zilis is currently living in Austin, where she is sometimes seen at events around the city, three people familiar with her said. In June, Musk confirmed to The New York Post that he had a third child with Zilis after Bloomberg reported on the child's existence.

When Musk is in town, neighbors, including some who haven't met him, say they can tell when someone is home because of the extra security stationed out front. Sometimes, they see a pet groomer pick up a small dog.

The neighbors say they don't know why Musk chose the neighborhood when he clearly values privacy. The area is densely populated and the community is not gated.

"I just keep thinking with that much money, he's probably got lots of whims and he'll do something else soon," said Jim Lewis, a retired rancher who lives near the house where Musk stays.

In September, pop star Taylor Swift endorsed Kamala Harris for president, signing her Instagram post "Childless Cat Lady." Musk posted on X, "Fine Taylor…you win…I will give you a child and guard your cats with my life."

People close to Musk believe he was only half joking.

This article originally appeared in The New York Times.