Long before Kristen Stewart took over tabloid covers and the "Twilight" franchise, the actress made her debut on the small screen in a Disney Channel Original Movie.

Though she didn't have any lines, nor was the stint credited, you can see eight-year-old Stewart in a white turtleneck, waiting on line at the water fountain in 1999's "Thirteenth Year." In honor of Flashback Friday, you can watch her at 34 minutes and 51 seconds into the clip below.

The TV movie, about an adopted teenager who turns into his true merman self on his 13th birthday, also stars Dave Coulier, better known as Uncle Joey from "Full House," as the boy's adoptive father.

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  • Brad Pitt, Pringles

  • Matt LeBlanc, Heinz Ketchup

  • Elijah Wood, Pizza Hut

  • Meg Ryan, AIM Toothpaste

  • Leonardo DiCaprio, Bubble Yum

  • Keanu Reeves, Corn Flakes

  • Morgan Freeman, Listerine

  • Sarah Michelle Gellar, Burger King

  • Dakota Fanning, Tide

  • Elle Fanning, Target

  • Demi Moore, Diet Coke

  • Ashley Tisdale, T-Mobile

  • Ben Affleck, Burger King

  • Evangeline Lilly, Live Links

  • Abigail Breslin, Toys "R" Us

  • Paul Rudd, Super Nintendo

  • Steve Carell, Brown's Chicken

  • Seth Green, Nerf

  • Bruce Willis, Seagrams Wine Coolers

  • Channing Tatum, Mountain Dew

  • Jack Black, Pitfall Video Game

  • John Travolta, Safeguard Bath Soap

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