The ex-partner of billionaire Elon Musk -- the Canadian singer who goes by the one name "Grimes" -- is criticizing him for bringing their four-year-old son known as "Lil X" to an Oval Office event earlier this week with President Donald Trump.

       President Donald Trump is joined by Elon Musk and his son X ？ A-Xii, as he signs a series of executive orders in the Oval Office at the White House on Feb. 11, 2025 in Washington.

       Kevin Lamarque/Reuters

       "This is X, and he's a great guy -- high IQ," Trump said at the top of Tuesday's event, chuckling and calling the boy a "high-IQ individual."

       In this May 7, 2018 file photo Elon Musk and Grimes attend the Heavenly Bodies: Fashion & The Catholic Imagination Costume Institute Gala at The Metropolitan Museum of Art in New York City.

       Dia Dipasupil/WireImage via Getty Images, FILE

       In a post on X later that day, Grimes responded to a comment about her son's "very polite" behavior, saying, "He should not be in public like this. I did not see this, thank u for alerting me. But I'm glad he was polite. Sigh."

       Musk's son 'Lil X' steals spotlight in the Oval Office

       Grimes and Musk share three children: X ？ A-12 or "Lil X," Exa Dark Sider？l, and Techno Mechanicus, also known as Tau.

       Tesla CEO Elon Musk walks with his son on his shoulders with Speaker Mike Johnson and Vivek Ramaswamy at the U.S. Capitol, Dec. 5, 2024, in Washington.

       Andrew Harnik/Getty Images

       Musk has been bringing his son to numerous events at the Capitol and elswhere around Washington for weeks now -- often carrying him on his shoulders. He was with Musk and the Trump family at Mar-a-Lago on election night.

       On Thursday, "Lil X," along with Musk's twins with Neuralink executive Shivon Zilis -- Strider and Azure -- were front and center at the tech mogul's meeting with India's Prime Minister Narendra Modi at Blair House, across the street from the White House.

       Elon Musk walks with his son X ？A-12 ahead of a meeting with Indian Prime Minister Narendra Modi at Blair House, in Washington, Feb. 13, 2025.

       Nathan Howard/Reuters

       Musk has 12 children in all, including six children from his previous marriage to author Justine Wilson, including twins and triplets.