Brooke Shields' daughter says she only found out her mom had been sexually assaulted while watching her tell-all documentary

• Brooke Shields' daughter said she found out about her mother's alleged sexual assault while watching her documentary.
• "I was learning about things the same time that the world was," Grier Henchy told People.
• Shields said she was sexually assaulted by an unnamed Hollywood executive when she was in her early 20s.

Brooke Shields' younger daughter said she found out about her mother's alleged sexual assault when she was watching last year's eye-opening documentary "Pretty Baby."