EXCLUSIVE: Madonna Reveals Her Twin Girls Just Started Listening to Her Music

The iconic singer is still having fun and reinventing herself at age 59.

Madonna is known for multiple talents, like singing, acting, and producing, and now she can add one more to the list--skincare expert!

ET caught up with the 59-year-old music icon at the New York City launch of MDNA, her new skincare line available at Barney's, where she opened up about her family life in Portugal.

"It's an experiment," she explains of the move to Lisbon. "I wanted to just go and experience another culture, music and art scene, and this one is phenomenal." 

But no matter where she moves, there's no escaping her global superstardom, something her four-year-old twins, Esther and Stella, are quickly learning.

"They go to school in Lisbon right now, and they're wondering why everyone's always coming up to them and saying, 'Is your mother, Madonna?' Like, why do they want to know who you are?"

Sounds like the newest members of the family have some catching up to do on mom's catalog.

"I mean, a lot of my kids have grown up seeing me in concert, but there are certain songs, like, the twins don't know anything," she said. "They heard  'Holiday' for the first time a month ago, so that was a fun moment for them."

David, though is a big fan of the 1983 hit. He rocked out to "Holiday" on his birthday, and Madonna couldn't help but share the video on her Twitter.

According to the proud mama, "He's a big fan, but not just of me. He's just-- he loves music."

As for her skincare line, the global superstar has a pretty good reason the new venture.

"I wanted to create a skincare line that was really customized for me and my stressful life and all in one," she said. "To grab one product from one line and a product from another line and find out that they got discontinued or you could only get this in Japan or you can only get this...in the U.K. So, it was developed out of necessity."

"And also with the work that I do, being onstage having to perform, sweating, like it's really rigorous and crazy putting on makeup, taking off makeup, sweating makeup off, you know what I mean? It's day-after-day traveling, being dehydrated and in airplanes, being sleep deprived," she added. 

And MDNA even has the seal of approval from her kids

"They just like the magnet pulling the mask off," Madonna shares. "They like doing it on their hands, they think it's magic and it is. So, it's a special treat."

However, Madonna is the first to admit there's more to looking great than a good moisturizer.

"I think feeling your best has a lot to do with being happy, being happy in your life," she continued. "That doesn't really have anything to do with skin. And also sleep. Which doesn't have anything to do with me, I'd like to sleep more, but more internal things and how you take care of yourself I think is the most important thing. Then the next step is having a good skincare regime and taking care of your skin."

Tune in to ET tonight for more from Madonna, and to check out her skincare line, click here.