Brooke Shields is getting real about raising teenagers.
When Shepard, 46, asked how old her two children are, Shields responded with a cheeky, "18 and a--hole." The Bless This Mess star then correctly guessed the age of the Beginning Is Now founder's youngest, Grier, who is 15 years old.
"It's so much fun," Shields said sarcastically about being a mom of a teen. "[Grier] just FaceTimed me about this dress that she wants to buy, and I'm trying to tell her what is the best plan of action to get said dress… then I get a text saying, 'I really don't appreciate the way you talk to me."
Shields shares Rowan, 18, and Grier with husband Christopher Henchy, whom she wed in 2001.
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Although Shields admitted that raising teenagers can be tough, that doesn't mean there aren't great moments both she and her husband share with their daughters.
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"With the girls, their dad is kind of their first love. It's special," she said of Rowan and Grier's relationship with their father. "But my girls tell me everything, and it usually ends up with, 'Don't tell dad.' "
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Additionally, Shields shared that she admires her 15-year-old daughter's fiery personality and has high hopes for her in the future. "The 15-year-old shocks me at times," she explained. "She's a social justice warrior. She can take an argument. I'd love her to be a prosecutor."
In November, Shields opened up about the special relationship she has with her youngest daughter, and revealed that she's a budding fashionista – and often borrows her clothes without telling her.
"My younger [daughter] is extremely into fashion," Shields told PEOPLE at Marie Claire's Power Trip: Off the Grid sponsored by United Explorer Card, Mercedes-Benz and Miraval Berkshires Resort & Spa.
"If I want to know where anything good that I have is, and I can't find it in my closet, I know exactly where to find it. It's her!"