More from EW
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Mila Kunis/Angelina Jolie, Gia (1998)
Twelve years before she shared an onscreen kiss with Natalie Portman in Black Swan, Kunis played the younger version of drugged-out, lesbian model Gia (Jolie). Acting is all about the preparation, right?
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Hayden Panettiere/Hilary Swank, The Affair of the Necklace (2001)
Seven years before she gained notice as the cheerleader who would save the world, Panettiere played the mini Jeanne de Saint-Rémy de Valois (Swank), a disgraced French aristocrat.
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Dakota Fanning/Reese Witherspoon, Sweet Home Alabama (2001)
Kewpie doll cuteness made Fanning a perfect choice to play young Melanie (Witherspoon) before she forgot her Southern roots.
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Jennifer Lawrence/Charlize Theron, The Burning Plain (2008)
Before she toiled to keep her family together in Winter's Bone, Lawrence played a character who not only killed her mother (accidentally) but then grew up to be a woman (Theron) who abandoned her own child.
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Mamie Gummer/Meryl Streep, Evening (2007)
In a role some would say she was born to play, Gummer personified the 1950s version of Lila, portrayed by her real-life mother Streep, in this film based on a Susan Minot novel.
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Brad Renfro/Brad Pitt, Sleepers (1996)
Renfro captured the hurt and abuse that a young Michael suffered as an inmate in a boys' prison, and helped us all understand why his grown-up self (Pitt) would seek revenge.
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Kate Winslet/Gloria Stuart, Titanic (1997)
Playing young socialite Rose aboard the doomed Titanic — told through the memories of her older self (Stuart) — helped launched Winslet onto the A list.
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Ewan McGregor/Alec Guinness, Star Wars (1977, 1980, 1983, 1999, 2002, 2005)
Okay, we acknowledge this is a bit of a cheat — this wasn't all in the same movie but McGregor did revive that same iconic fount-of-wisdom quality that Guinness brought to Obi Wan Kenobi in the earlier films.
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X-Men (2006, 2011) James McAvoy/Patrick Stewart Michael Fassbender/Ian McKellen Nicholas Hoult/Kelsey Grammer Jennifer Lawrence/Rebecca Romijn
The upcoming X-Men: First Class is all about the young'uns, with a new crop of actors taking on Professor X, Magneto, Beast, and Mystique.
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Robert DeNiro/Marlon Brando, The Godfather Trilogy (1972, 1974)
Another sequel to add to the mix but really, who could played the don (Brando) as an up-and-comer better than DeNiro?
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River Phoenix/Harrison Ford, Indiana Jones and the Last Crusade (1989)
Before he met with his untimely real-life passing, Phoenix was a young Indy and showed us how our adventurous professor (Ford) got his scar.
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Saoirse Ronan/Vanessa Redgrave, Atonement (2007)
Big blue eyes and an ethereal look went a long way in Ronan's portrayal of the meddling Briony, who would age into a thoroughly remorseful elderly woman (Redgrave). Well, that and a wealth of talent.
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Ewan McGregor/Albert Finney, Big Fish (2003)
Truth may be fuzzy in this tale, but what's bright and clear is McGregor's gleeful romp as the young Edward Bloom, even if we don't know how he becomes the crabby storytelling dying patriarch (Finney)
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Kirsten Dunst/Samantha Mathis, Little Women (1994)
Dunst's focused young Amy who heads off live with Aunt March, then grows up to be quite the self-absorbed beauty (Mathis).
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Tammy Blanchard/Judy Davis, Life with Judy Garland: Me and My Shadows (2001)
Blanchard strode down the yellow-brick road that marked the beginning of the legendary Garland's career, while Davis inhabited the diva's later years.