Madonna worries about "absolutely everything".
Madonna
The 'Living for Love' hitmaker - who has Lourdes, 20, Rocco, 16, David, 11, and Mercy, 10 - admits her family is her top concern.
She said: "I worry about absolutely everything. I worry about my kids all day long. I worry about my health. I worry about whether I'm going to get things done in time.
"I worry about every project I'm working on. I worry about whether I'll get to sleep at night. I worry about the state of the world. There isn't anything I don't worry about."
And the 58-year-old singer says her family is "everything" to her and she has great pride in her kids' achievements.
She added: "My family is everything. I will go to war for them. Whatever I'm fighting for, it's for my daughters and my sons. I want them to have a good future. I've created an unconventional family and we have discussions at the dinner table about all sorts of things.
"My 11-year-old son can speak eloquently about Malcolm X and Martin Luther King and Nelson Mandela and James Baldwin. My daughter Mercy plays the piano and can talk to you about Nina Simone. I'm really proud of that."
Madonna's children regularly feature in her Instagram pictures but they always give her "permission" to include them in her posts.
She added: "When I post their things, they give me permission. A lot of times they'll send me pictures and say, 'Please don't post this,' and I won't. They have private accounts, and I respect that. I also consider my children part of my work and the work that we do together."
And the pop legend feels "so lucky" to have children David and Mercy with her but she desperately wants to improve the lives of other children in their native Malawi too.
She told the new issue of Billboard magazine: "I've been working in Malawi for over a decade. I have a huge commitment and love for the country and I will never desert them. I adopted my two children that I'm so lucky to have living in my house right now."
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