It looks like Rumer Willis is one doting daughter. The oldest child of amicable exes Demi Moore and Bruce Willis recently opened up about her mother’s “deeply candid” memoir, titled Inside Out. To help make the wait until its September release easier to deal with, she is giving fans some insight into the highly anticipated book.

“I actually finished it not too recently and I’m so incredibly proud of her,” Rumer, 30 revealed to Entertainment Tonight at the Los Angeles premiere of Once Upon a Time in Hollywood on Monday, July 22. “It’s so beautiful and she shows such courage and vulnerability.”

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The Empire actress teased that fans would get an exclusive glimpse inside the private life of the 56-year-old star. “I think [it shows] a depth inside of herself that no one has really seen yet, which I’m really excited for people to get to know that side of her,” Rumer marveled to the outlet, perhaps referring to her mom’s battles with “addiction, body image issues and childhood trauma” that were mentioned in a press release from HarperCollins in April.

The brunette beauty also talks about her three failed marriages. From 1980 to 1985, Demi was married to musician Freddy Moore. In 1987, she then married Bruce and welcomed three daughters, Rumer, Scout Willis, 28, and Tallulah Scout, 25. Sadly, the two divorced in 2000 and Demi moved on with Ashton Kutcher, who she married in 2005 but split eight years later in 2013.

Rumer Willis Makes Her Debut As Roxie Hart In Broadway's "Chicago"
Bruce Glikas/FilmMagic

“In this emotionally charged memoir, she opens up about her career and personal life — laying bare her defining tumultuous relationship with her mother, her marriages, her struggles balancing stardom with motherhood, and her journey toward open heartedness,” the press release read. “Inside Out is a story of survival, success, and surrender — as well as resilience: a wrenchingly honest portrayal of one woman’s at once ordinary and iconic life.”

When Demi’s memoir first made headlines in April, a source told Closer Weekly about the Striptease actress’ excitement. “Demi is ready to relive her extraordinary life and she’s including all the highs and lows, which will include her big break on a soap opera, joining the infamous Brat Pack and being the highest paid actress in Hollywood,” the insider exclusively dished to Closer Weekly at the time.

Demi’s book, Inside Out, will be available wherever books are sold on Tuesday, September 24!