Demi Lovato recently inked a multi-book deal that will include a memoir. While it might seem premature to pen an autobiography at age 21, she's not the only under-30 celeb to have done so.

Miley Cyrus, "Miles to Go" (2009)
Age when published: 16
miley

Farrah Abraham, "My Teenage Dream Ended" (2012)
Age when published: 21

farrah

Justin Bieber, "First Step 2 Forever: My Story" (2010)
Age when published: 16

bieber

Gabby Douglas, "Grace, Gold, and Glory My Leap of Faith" (2013)
Age when published: 17
gaby

Britney Spears, "Heart To Heart" (2000)
Age when published: 18

britney

Paris Hilton, "Confessions of an Heiress" (2004)
Age when published: 23

paris

Drew Barrymore, "Little Girl Lost" (1990)
Age when published: 15

drew

Jodie Sweetin, "unSweetined: A Memoir" (2019)
Age when published: 27

jodie

Kelly Osbourne, "Fierce" (2009)
Age when published: 24

kelly

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  • Snooki, "A Shore Thing"

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  • Lauren Conrad, "L.A. Candy"

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  • Lauren Conrad, "Sweet Little Lies"

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  • Nicole Richie, "The Truth About Diamonds: A Novel"

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  • Khloe and Kourtney Kardashian, "Dollhouse"

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  • Ethan Hawke, "Ash Wednesday"

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  • Pamela Anderson, "Star: A Novel"

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  • Madonna, "The English Roses"

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  • Courtney Thorne-Smith, "Outside In"

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  • Julianne Moore, "Freckleface Strawberry"

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  • Sharon Osbourne, "Revenge"

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  • James Franco, "Palo Alto: Stories"

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  • Steve Martin, "An Object of Beauty"

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  • Hugh Laurie, "The Gun Seller"

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  • Tyra Banks, "Modelland"

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