Will Sage Astor-Elon Musk Shares Rare Photo of His and Grimes' Son X in Honor of His 4th Birthday

Elon Musk's eldest child with ex Grimes,Will Sage Astor X Æ A-Xii, is all smiles in a new pic his dad shared on his fourth birthday.

The billionaire Tesla CEO posted the photo of the boy, nicknamed X, on the social media platform he owns, X, formerly Twitter. Musk captioned the post, which shows the child sitting on what appeared to be a reception desk, "Lil X turns 4 today on May 4th."

The Space X founder, a father of 11 and one of the top three richest people in the world, rarely shares pics of his kids on social media. He has occasionally been photographed out with X, most recently in March during a visit to Tesla's electric car plant in Gruenheide, Germany.

In addition to X, Musk and Grimes, who broke up in 2022, are also parents to Exa Dark Sideræl, or Y, 2, and Techno Mechanicus, or Tau, whose birth was confirmed in 2023.

Musk, 52, also fathered six children with ex-wife Justine Wilson Musk: Twins Vivian and Griffin, 19, triplets Kai, Damian, and Sax, 18, and eldest child, son Nevada, who tragically passed away at age 10 weeks in 2002.

In 2021, the businessman welcomed twins Strider and Azure. with Neuralink executive Shivon Zilis. She has occasionally shared pics of their kids on her own X account.

In April, Musk jokingly reflected on his parenting journey on X. "Whoa," he wrote, "I just realized that raising a kid is basically 18 years of prompt engineering."

Read on to find out more about Musk's complicated family tree...

Maye was born in Saskatchewan, Canada and emigrated with her parents to Pretoria, South Africa in 1950, when she was 7. She and Elon's father, Errol, split in 1979.

After Elon moved to Canada at age 17, Maye obtained Canadian citizenship by birthright and moved there too, as did his siblings.  There, she established a dietician practice and became President of the Consulting Dieticians of Canada, per Forbes. She also worked as a model.

In 2019, after Elon sold his company Zip2 to Compaq for more than $300 million, he bought his mom an apartment in New York City, where she lived for 13 years and continued her modeling career. She is signed to the IMG Models agency. 

"I brought my children up like my parents brought us up when we were young: to be independent, kind, honest, considerate and polite," Maye wrote in an essay for CNBC. "I taught them the importance of working hard and doing good things."

Elon's father is an engineer and like Elon, was born in South Africa. In the 2015 biography Elon Musk: Tesla, SpaceX and the Quest for a Fantastic Future, author Ashlee Vance wrote that Elon and his dad had a difficult relationship. In an emotional 2017 Rolling Stone interview, Elon criticized his father and talked about his upbringing, saying that after his parents split, he moved in with his dad, which, he said, "was not a good idea."

However, Errol told Rolling Stone, "I love my children and would readily do whatever for them."

In a 2015 Forbes interview, Elon's dad said he used to take his kids on trips overseas. "Their mother and I split up when they were quite young and the kids stayed with me," he said. "I took them all over the world."

After divorcing Elon's mother Maye, Errol married Heide, whose daughter Jana Bezuidenhout was 4 years old at the time. Errol and Heide went on to have two daughters together before they, too, broke up. 

Years later, Jana reached out to Errol following a breakup. "We were lonely, lost people," Errol explained in a 2018 interview with The Sunday Times. "One thing led to another—you can call it God's plan or nature's plan." Either way, the duo welcomed son Elliott in 2017 and then a baby girl in 2019. As Errol put it to The Sun, "The only thing we are on Earth for is to reproduce. If I could have another child I would. I can't see any reason not to."

Kimbal, born in 1972, is a restauranteur. He is the founder of The Kitchen, a collective of five restaurants that source directly from local farmers, Forbes reported in 2018. He also runs a non-profit, Big-Green, that has built 200 learning gardens in schools across the U.S., the outlet said.

Tosca, born in 1974, is a filmmaker. In 2017, she founded Passionflix, a female-focused streaming service that targets the billion-dollar romance novel industry, according to Forbes. 

Elon and Canadian-born Justine, his college sweetheart from Queen's University in Ontario, married in 2000.  In a 2010 article she penned for Marie Claire, titled I Was a Starter Wife: Inside America's Messiest Divorce, Justine said that while dancing at their wedding reception, Elon told her, "I am the alpha in this marriage."

"I shrugged it off," Wilson wrote, "just as I would later shrug off signing the postnuptial agreement, but as time went on, I learned that he was serious."

The two welcomed their first child, son Nevada Alexander, in 2002. The baby died at age 10 weeks from Sudden Infant Death Syndrome (SIDS). "Nevada went down for a nap, placed on his back as always, and stopped breathing," Justine wrote in her article.

The couple pursued IVF to conceive again and went on to welcome five more kids: Twins Vivian and Griffin and triplets Kai, Saxon and Damian. 

In 2008, Elon filed for divorce. They share custody of their children. 

In a July 2022 snap shared on social media, Elon revealed he took his oldest sons to meet Pope Francis. While he was "honored" to meet the head of the Catholic church, Elon added of his 'fit, "My suit is tragic." 

That same year, Elon's daughter Vivian filed a petition to change her full name in accordance with her new gender identity, writing, "I no longer live with or wish to be related to my biological father in any way, shape or form."

Elon and Tallulah—who played host greeter Angela on HBO's Westworld—married in 2010.  "It all happened very fast," she told CBS News. "We were engaged after, I think, two weeks of knowing each other." 

The two divorced in 2012, then remarried a year later before divorcing again in 2016.

Elon and Amber went public with their romance in early 2017, a year after she filed for divorce from Johnny Depp and Elon ended his second marriage to his second wife Tallulah Riley. Months later, Elon and Amber called it quits. 

"I just broke up with my girlfriend," Elon told Rolling Stone at the time. "I was really in love, and it hurt bad...Well, she broke up with me more than I broke up with her, I think."

Elon and the singer dated on and off for about four years, starting in 2018. In September 2021, Elon told Page Six that he and Grimes "are, I'd say, probably semi-separated," adding, "It's mostly that my work at SpaceX and Tesla requires me to be primarily in Texas or traveling overseas and her work is primarily in LA. She's staying with me now and Baby X is in the adjacent room."

In a March 2022 interview with Vanity Fair, the singer said she and Elon "live in separate houses" and are "best friends."

She later tweeted, "Me and E have broken up *again* since the writing of this article haha, but he's my best friend and the love of my life, and my life and art are forever dedicated to The Mission now." 

When news broke in September 2023 that the couple share three children together, the "Crystal Ball" singer confirmed that, yes, their most recent addition Techno Mechanicus had joined son X Æ A-12, 3, and daughter Exa Dark Sideræl, 20 months.

In 2020, Elon and then-girlfriend Grimes welcomed their first child together, a son. They soon modified the spelling of his name in order to meet California's legal guidelines, which only permit letters from the English alphabet. Switching over to roman numerals, the parents agreed to spell his name, X Æ A-Xii.

"X, the unknown variable," Grimes explained on Twitter. "Æ, my elven spelling of Ai (love &/or Artificial intelligence) A-12 = precursor to SR-17 (our favorite aircraft). No weapons, no defenses, just speed. Great in battle, but non-violent." 

Grimes continued, "A=Archangel, my favorite song" adding a rat and sword emoji. "Metal rat."

In her 2022 Vanity Fair interview, Grimes revealed she and Elon privately welcomed a baby girl via surrogacy.

"Exa is a reference to the supercomputing term exaFLOPS (the ability to perform 1 quintillion floating-point operations per second)," she said. "Dark, meanwhile, is the unknown. People fear it but truly it's the absence of photons. Dark matter is the beautiful mystery of our universe.'"

Sideræl—pronounced "sigh-deer-ee-el," is "the true time of the universe, star time, deep space time, not our relative earth time," and a nod to her favorite Lord of the Rings character, Galadriel, who "chooses to abdicate the ring."

A year later, the New York Times' Sept. 9 review of Walter Isaacson's biography Elon Musk stated that Elon and Grimes share three children, not two as previously believed. The on-again, off-again couple at one point welcomed a child named Techno Mechanicus, nicknamed Tau, a report Grimes confirmed soon after.

"I wish I could show u how cute little Techno is," she wrote on X, "but my priority rn is keeping my babies out of the public eye, Plz respect that at this time."

In 2022, Business Insider published court documents that stated Elon welcomed twins with Neuralink executive Shivon Zilis in November 2021. The babies were reportedly born in Austin, Texas, where the businessman lives. He also seemingly weighed in on the report on Twitter, writing, "Doing my best to help the underpopulation crisis. A collapsing birth rate is the biggest danger civilization faces by far."

"Mark my words," he added, "they are sadly true."

In September 2023, a Time magazine cover story, adapted from biographer Walter Issacson's book about Elon, revealed that their twins were named Strider and Azure.

In 2022, Business Insider published court documents that stated Elon welcomed twins with Neuralink executive Shivon Zilis in November 2021. The babies were reportedly born in Austin, Texas, where the businessman lives.

He also seemingly weighed in on the report on X, writing, "Doing my best to help the underpopulation crisis. A collapsing birth rate is the biggest danger civilization faces by far."

"Mark my words," he added, "they are sadly true."

In September 2023, a TIME magazine cover story, adapted from biographer Walter Issacson's book about Elon, revealed that their twins were named Strider and Azure.