On a quiet, tree-lined street lined with multimillion-dollar properties, one home stands out: a 14,400-square-foot mansion that Elon Musk, 53, plans to turn into an unusual family compound.

Just behind the mansion is another six-bedroom mansion. The combined value of the two properties is around $35 million. When in Austin, Musk often stays at a third mansion about a 10-minute walk away.

That’s three mansions, three mothers, 11 kids, and one mysterious billionaire dad. The fear of falling birth rates is even driving Musk to expand his already unusual family.

“I’m doing my best to confront the population crisis. Falling birth rates are the biggest threat civilization has ever faced. Mark my words, this is the sad truth. I hope you have big families, and I congratulate those of you who have big families,” Musk proudly said.

As an advocate of in vitro fertilization, Musk has placed his faith in increasing the world’s population. He has even donated his sperm to friends and acquaintances, including former vice presidential candidate Nicole Shanahan.

Over the past two years, Musk has become increasingly obsessed with what he sees as a threat. He believes that a global population collapse is imminent and that humanity will be wiped out. Demographers say that apocalyptic scenario is unlikely, but the billionaire has encouraged his fans to have as many children as possible.

“Children should be treated as a national emergency,” Musk tweeted in June.

Musk is now based in Pennsylvania, immersed in his presidential campaign and spending tens of millions of dollars to fund Trump’s campaign. A Trump victory would make Musk the most powerful private citizen in the country.

One citizen is anxious to create a family compound. One of the mothers, Shivon Zilis, CEO of Musk’s brain technology startup Neuralink, has moved into the mansion with her children. Claire Boucher, the musician better known by her stage name Grimes, has so far avoided her ex-husband.

Musk’s views appear to be similar to those of his father, Errol Musk. The 78-year-old has seven children with three women.

“You raise horses,” Errol Musk said in an interview in September. “Humans are the same. If you have a good father and a good mother, you will have special children. If you don’t have children, I feel sorry for you.”

Earlier in 2021, shortly after moving from California to Texas, Musk anonymously donated $10 million to the University of Texas at Austin. This was Musk’s largest-ever donation to education, helping to establish a research group called the Population Wellbeing Initiative (PWI) with a mission to conduct quantitative research in social science. The ultimate goal is said to be to legitimize the view that “low birth rates are a threat to long-term prosperity.”

Many experts believe that Musk has used social media extensively to amplify birtherism. The billionaire has always emphasized that the rate of population decline is getting worse, and so he himself is racing to…have more children.

“Look at the numbers. If people don’t have more children, civilization will collapse,” Musk warned. “A lot of people think the world is too crowded. I think it’s the exact opposite.

Look at the actual numbers today, if people don’t have more children, civilization will collapse. Remember what I said. The foundation of the economy is labor. If there are not enough workers, the economy will suffer. I want to emphasize that we don’t have enough people.”

Elon Musk is not the only billionaire worried about the declining birth rate. Jack Ma, Chairman of Alibaba Group, agrees that people need to have more children.

“The first KPI of marriage is to have results, to have products. What is the product? It is children,” said Jack Ma. “Getting married is not about accumulating wealth, not about buying a house or a car, but about having children together. Have more children!”