Grimes' mother is accusing Elon Musk of preventing his and her daughter's three children from being able to travel to see their ailing maternal grandmother.

Sandy Garossino, a Canadian journalist, published a letter to the Tesla CEO on his social media platform X July 27. She made her comments amid an ongoing custody battle between her daughter and the billionaire, who share kids X Æ A-Xii, 4, Exa Dark Sideræl, 2-and-a-half, and Techno Mechanicus, 2.

"Dear Elon @elonmusk. It was nice seeing you on Father’s Day. I hope you got the card that I helped X make," Grimes' mom began. "He was so proud of it."

She continued, "I’m writing here as the only way I have to reach you. As you know, my 93 year old mother is now at end-of-life palliative care. She yearns to see and hold Claire’s children one last time. Especially the youngest, whom she has not yet met."

"She was thrilled for the kids’ planned visit to celebrate her birthday this weekend. Today. But those hopes were crushed when the trip was canceled," Grimes' mother continued. "I am alarmed to learn that the children cannot come as you are withholding them and their needed passport documents from Claire."

"It was even more troubling to see you and X on television at the Olympics in Paris yesterday, after your DC trip earlier in the week," Garossino wrote in her letter to Musk. "Where are the other children, and with whom? They are scheduled to be with their mother. They were expected here in Canada."

Grimes' mom continued, "I write with a grandmother’s plea, asking you to honour your agreement, return the children, and provide the documents they need to see their great grandmother before she passes."

Garossino added that "some moments in life last forever, and we get no second chances. Family is priceless."

"Please Elon, I beg you," she wrote. "This is so painful for my mother, and concerning for the kids. Time is of the essence now."

Grimes and Musk—who split in 2022 after four years of dating—have been locked in a legal dispute over their kids since October, when the musician filed a petition against him to establish parental rights, NBC News had reported. Their dispute has played out in both California and Texas courts, with the cases sealed from public access. 

Meanwhile, following her mother's public plea, Grimes has received public support from Musk's estranged daughter Vivian Jenna Wilson, who he shares with ex-wife Justine Wilson.

The 20-year-old reposted Garossino's X comments on the Meta-owned Threads app and accused her father of keeping his and Grimes' children, "away from their mother during the most important developmental period in a child’s life."

She alleged that the kids "are stuck in a house thousands of miles away without their mother," adding, "This is not the first time this has happened and if nothing changes, likely not the last."

Musk and Grimes have not commented on Vivian's remarks, which she made days after the musician expressed support for her amid her transgender journey and a public feud with her dad, who said in a recent interview that his "son" was “dead, killed by the woke mind virus.”

"Last time I checked," she wrote on Threads July 22. "I am, indeed, not dead."

Musk, a father of 12, has not responded to Garossino or Vivian's remarks. E! News has reached out to the X CEO and Grimes for comment and has not heard back.

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

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 Musk, split in 1979.

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

In 2019, after Elon sold his company Zip2 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 after being 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.

Though Errol said in a 2015 Forbes interview that he used to often take his kids on trips overseas—"Their mother and I split up when they were quite young and the kids stayed with me. I took them all over the world."—his relationship with Elon isn't picture perfect.

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."

Following his divorce from 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 of her own. "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 became romantic and 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 and the founder of The Kitchen, a collective of five restaurants that source directly from local farmers. 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. 

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 faced an unthinkable tragedy when their baby boy Nevada Alexander died at 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.

In 2022, Elon revealed he took Griffin and the triplets 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." 

Also in 2022, Griffin's twin sister 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."

In July 2024, Elon spoke out about his daughter's transition. "I lost my son, essentially," he said in a Daily Wire interview with Jordan Peterson, adding that his child, who he referred to by her birth name, was "dead, killed by the woke mind virus."

He also alleged that he was "tricked" into signing medical documents granting Vivian gender-affirming treatments.

She disputed his comments. "He was not by any means tricked," she said in an NBC News. "He knew the full side effects."

Elon and Talulah—who starred 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. In June 2024, she wed Love Actually alum Thomas Brodie-Sangster.

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 Talulah. Though their relationship didn't last long.

"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 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."

However, in March 2022, she told Vanity Fair that they "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.

In 2020, Elon and 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, according to mom, "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."

Walter Isaacson revealed in his biography Elon Musk that Exa was born in December 2021 via surrogate.

The book also stated that around Father's Day 2022, the on-again, off-again couple welcomed a child named Techno Mechanicus, nicknamed Tau, also via surrogate. The biography includes a photo, dated June 2022, of Elon feeding the baby boy.

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

Walter Isaacson wrote in his 2023 biography Elon Musk that the twins' full names are Strider Sekhar Sirius and Azure Astra Alice.

In 2024, Elon and Zilis welcomed their third baby together. The billionaire confirmed the news in June 2024, telling Page Six, "All our friends and family know," adding, "Failure to issue a press release, which would be bizarre, does not mean 'secret.'"

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