Madonna shared an Instagram post on Sunday, Jan. 3, that seemed to refer to her problems with her son Rocco Ritchie. Credit: Dimitrios Kambouris/Getty Images

Madonna seemingly referenced an ongoing custody problem with her son Rocco in an Instagram post she shared on Sunday, January 3.

"Preach Nietzsche," the pop queen, 57, captioned a quote from German philosopher Friedrich Nietzsche. "As we enter the 7 weeks of exile and redemption."

The quote reads, "One way of measuring the strength of an attacker is by looking at the sort of opponent he needs. You can always tell when something is growing because it will go looking for powerful adversaries or problems."

The "Material Girl" singer has been in a custody battle with her ex-husband, British director Guy Ritchie, 47, over their son Rocco, 15. 

The teen reportedly refused to return to his mom in the U.S. after visiting his father in London, which led to a hearing in a Manhattan court. On December 23, a judge ordered Rocco to return to NYC, but Ritchie's attorney pushed back. 

“Rocco has expressed very clearly that he does not want to return to New York," attorney Eric Buckley said.

While Madonna went on to post a sweet pic of Rocco over Christmas, Rocco subsequently blocked his superstar mom from viewing his Instagram account, U.K. newspaper The Sun reports.

Merry X-mas to the Sun-shine of my Life! ⭕️❌⭕️⭕️❌⭕️❌⭕️❤️❤️

A photo posted by Madonna (@madonna) on

And it's reportedly not just Rocco who is rebelling against his mother. His sister Lourdes, 19, is also battling with Madonna, according to the New York Post's Page Six.

Sources told the publication that the kids feel their mom is "too controlling" and that they both "crave stability," but their mother's touring schedule has made that difficult.

Madonna and Ritchie divorced in November 2008 after eight years of marriage. Along with Rocco, they share son David, 10. She is also mom of Lourdes (with ex Carlos Leon) and Mercy, 9. 

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