Amid her custody battle over son Rocco Ritchie, Madonna is leaning on her daughter Lourdes Leon more than ever.

According to a new report, Lourdes, 19, is “very concerned” her 57-year-old mom could be on the verge of a “stress-induced meltdown” due to her ongoing custody disagreements with Rocco’s father, Guy Ritchie.

“Lourdes is very concerned about her mother. Madonna has no official access or way of knowing what’s going on in Rocco’s life. She also can’t get direct contact with Guy. He wants to conduct all their business through lawyers,” a source close to the singer told The Sun.

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“Madonna is so proud of Lourdes, she believes she is proof of what a brilliant [mom] she was because she is now at university,” the insider said, adding Lourdes is currently acting as a mediator between her mother, Rocco, 15, and Guy, 47. Reports first surfaced that Madonna and Guy are involved in a messy custody battle over Rocco in December 2015.

madonna and guy ritchie

Madonna and Guy in September 2008.

The former couple were previously married from 2000 until 2008. They welcomed Rocco in 2000 and adopted their son David, 10, in 2005. Madonna welcomed Lourdes in 1996 with her then-boyfriend, Carlos Leon, and is also a mom to daughter Mercy, 10, whom she adopted as a single parent in 2006. Guy additionally has three kids — Rafael, 4, Rivka, 3, and Levi, 1 — with his wife, Jacqui Ainsley, 34.