Elon Musk and Grimes have three children together.
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- Grimes' mother addressed Elon Musk directly in a series of X posts on Saturday.
- Sandy Garossino said the former couple's children couldn't visit Grimes' family because Musk is "withholding" them.
- Musk and Grimes are involved in a custody battle involving their three children.
Grimes' mother says Elon Musk is "withholding" the former couple's children from the rest of the family.