Demi Moore, 56, took to Instagram on Friday sharing an old photo, saying it showed her when she was a teenager.

In the snap, Moore wore a yellow and white crop top paired with light pink shorts. She kept her signature dark tresses up and kept her makeup minimal.

DEMI MOORE PENNING 'A WRENCHINGLY HONEST' MEMOIR 

"Baby ‘mi #tbt circa 1975 or 76," she captioned the pic along with a series of hashtags promoting her new memoir "Inside Out."

Moore's book – scheduled to be released on Sept. 24 – is "deeply candid and insightful," according to publisher HarperCollins.

Per the publisher, Moore writes openly about everything from her "tumultuous relationship" with her mother, from whom she was long estranged, to her three marriages, among them to Bruce Willis and Ashton Kutcher.

DEMI MOORE ATTENDS EX BRUCE WILLIS' VOW RENEWAL TO WIFE EMMA HEMING 

"Throughout her rise to fame and during some of the most pivotal moments of her life, Moore battled addiction, body image issues, and childhood trauma that would follow her for years — all while juggling a skyrocketing career, celebrity status, and raising a family," HarperCollins said when the book was announced last month.

"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."

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The announcement added: "'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."