Brooke Shields’ Younger Daughter ‘Had No Idea’ Mom Was Sexually Assaulted Until She Saw Pretty Baby Doc: ‘I Was Shocked’ (Exclusive) 

“Part of being a mom is learning from your kids,” Brooke Shields tells PEOPLE in an exclusive interview with her daughters, Rowan, 21, and Grier, 18, in this week’s cover story. Such was the case when Pretty Baby, the documentary about her life, came out last year.

The doc explored the one-of-a-kind life of the actress and beauty icon and her six-decade-long career. It was also the first time she revealed she had been sexually assaulted in her early 20s by a powerful Hollywood figure, whom she chose not to name. 

While her daughter, Rowan, was aware of the assault, Grier, was not.

“I didn’t prepare her,” says Brooke, 59. “It was a miscommunication. I had explained it was an exploration of sexualization of women in my industry but I was naively thinking that because we had such a solid, healthy, fairly normal existence and I’m not completely damaged that she would say, ‘Wow you’ve come through a lot but look where we are today.’” 

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But it was a shock for her younger daughter. 

“I was learning about things the same time that the world was and I just took it more deeply and personally,” says Grier. “I couldn't even get through it.”

Says Brooke, “I told her 'but there’s a happy ending' and she said, ‘I will never be okay with thinking something bad happened to you.’” 

“She ended up missing the happy part,” Brooke says, who shares both daughters with her comedy writer husband Chris Henchy. “She felt helpless, and just as a mom, we make mistakes and sometimes we make assumptions.” 

As she reflects now, “To see the documentary or to see your parents as a public figure that other people have opinions on is just an odd situation. I’ve learned a lot by listening to them.”

For more on Brooke Shields and her daughters, pick up the new issue of PEOPLE.