Grimes thinks Elon Musk should stay grounded.

The singer took a not-so-veiled swipe at her ex, who has often talked about his plans to visit Mars one day, with an emphatic endorsement of Olivia Rodrigo’s recent thoughts on dating red flags.

"This is a very oddly specific question that I ask guys on first dates," Olivia’s recent quote shared by PopCrave read. "I always ask them if they think that they would want to go to space. And if they say yes, I don’t date them."

The "Brutal" singer, who is dating actor Louis Partridge, continued, "I just think if you wanna go to space, you’re a little too full of yourself. I think it’s just weird."

Grimes, who shares X Æ A-Xii (aka X), 4, Exa Dark Sideræl (aka Y), 2, and Techno Mechanicus (aka Tau), 2, with Elon, agreed with the quote in her response, saying, "It's true. Only women should be going to space."

The singer's cheeky response elicited a wide array of responses, including one who sarcastically asked, "what happened last time you dated a guy who wanted to go to space?"

Another user joked that Grimes would know, as she has "the most experience" dating a man who wanted to go to space.

The musician's comments come amid her ongoing custody battle with Elon, who she dated on and off for four years before breaking up in 2022. 

Grimes—whose real name is Claire Boucher—filed a petition against him last October to establish parental rights, yet not much else is known about the case, which has been sealed from public access.

Back in July, Grimes' mother Sandy Garossino accused Elon of withholding her three grandchildren from her daughter and pleaded with him to let her take them to see her own ailing mother.

"I’m writing here as the only way I have to reach you," she wrote in a letter posted to X. "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 continued, "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. I am alarmed to learn that the children cannot come as you are withholding them and their needed passport documents from Claire."

Sandy added that Grimes' three children had been "scheduled to be with their mother" at the time of posting, yet it was unclear who they were staying with at the time, with Elon—a dad of 12—traveling to Paris for the Olympics.

She finished, "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."

Elon's estranged daughter Vivian Jenna Wilson, who he shares with ex Justine Wilson, backed up Sandy's claims with a post of her own.

"Elon has been illegally and continuously keeping their children, her children, away from their mother during the most important developmental period in a child’s life," the 20-year-old wrote on Threads. "While Elon has been irresponsibly partying across the ocean in the very country he’s spitting contemptuous poison about, Grimes’ children are stuck in a house thousands of miles away without their mother."

She continued, "This is potentially irreversibily damaging to a child’s psyche and is, without question, a despicable form of abuse. This is not the first time this has happened and if nothing changes, likely not the last."

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