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You probably think the Modern Family star can't drink yet, let alone own a driver's permit, but Hyland is a full-fledged adult — she'll turn 24 on Nov. 24.
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Page was totally believable as a teen in Juno, but the Oscar nominee was 20 when the movie was released and turned 27 on Feb. 21.
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Does Wood have some Dorian Gray deal going on? He's been acting since he was 8 and looks like he's been frozen in time as a 13-year-old. But the erstwhile Frodo is a grown-up: He turned 33 on Jan. 28.
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The erstwhile Rory Gilmore still looks like she could attend Chilton, but Bledel will be 33 on Sept. 16.
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Lawson may not be a household name, but the actress, who turned 35 on March 20, has been convincingly playing high-schoolers for 20 years, first on Saved By the Bell: The New Class and most recently on Pretty Little Liars.
6 of 28 Steve Granitz/WireImage
Did Hannigan learn some age-defying witchcraft during her years on Buffy the Vampire Slayer? The How I Met Your Mother star turned the big 4-0 on March 24, but looks as youthful as she did when she was roaming the halls of Sunnydale High.
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The Big Bang Theory star Parsons may look like a Caltech undergrad, but he's actually turned 41 on March 24. That kind of age defiance deserves some theorizing of its own!
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Between his boyish features and disheveled haircut, surely the Revenge star is in his mid-20s — maybe early 30s — right? Nope! The former model turned 42 on May 14.
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Perhaps more surprising than the fact that Vergara will turn 42 on July 10 is that the Colombian beauty has a 21-year-old son!
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Maybe it's her youthful style, but the No Doubt frontwoman and new Voice coach still seems like "Just a Girl" to us. In reality, though, Stefani will be 45 on Oct. 3.
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Time arguably has stopped for Dash, who turned 47 on Jan. 20. That means she was 28 when Clueless came out in 1995 — and she definitely did not look it.
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We'd be brawling over Berry too if she knows the secret to looking forever young. Can you believe she'll be 48 on Aug. 14?
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Those piercing baby blues, that gorgeous mop of brown hair, those cheekbones. Lowe doesn't look that much different than he did during his Brat Pack heyday, but the Parks and Recreation alum turned 50 on March 17.
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Gracie Hart, er, Gracie Lou Freebush, only got Miss Congeniality honors, but Bullock, who turns 50 on July 26, could definitely take the Miss United States crown with her ageless beauty, not to mention winning personality.
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Has Loughlin aged a day since Full House? She turns 50 on July 28, but if you ask us, she looks younger now than she did then.
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Depp is a chameleon on-screen, but off-screen? We can hardly spot a wrinkle on the heartthrob, who turned 51 on June 9.
17 of 28 Steve Granitz/WireImage.com
Something was definitely in the Full House waters, or at least in Jesse and Becky's attic, because Stamos looks as dishy as ever — and now sans mullet! He will be 51 on Aug. 19. Have mercy!
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Raising a brood of six is sure to add a few more gray hairs, but People magazine's first two-time Sexiest Man Alive still looks as dreamy as he did when the world first laid eyes on his baby blues more than 20 years ago, which makes it all the more shocking that he'll turn 51 on Dec. 18.
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Katie Holmes blindsided Cruise by filing for divorce days before he turned 50 on July 3, 2012, but Father Time has been much kinder to the star, who not only looks younger than us, but can still kick our ass any day of the week.
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If you've got it, flaunt it! McDermott, who turns 53 on Oct. 26, showed off a chiseled physique — and butt! — on American Horror Story that could rival those of studs half his age.
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The Karate Kid still looks like just that: a kid. But Macchio will turn 53 on Nov. 4 and definitely feels his age. "Don't let the gift-wrapping fool ya!" he told TVGuide.com in 2011. "It's just good genes. But the working parts are chronologically the age you look up."
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The Fabulous Baker Boys? More like The Fabulous Michelle Pfeiffer! The blonde bombshell turned 56 on April 29 and looks as smokin' hot as she did when she writhed on top of a piano "Makin' Whoopee." We're pretty sure she'd still stop traffic in that Catwoman suit too.
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This supermodel has super-genes. Flawless and cover-ready as ever, Iman turns 59 on July 25 and doesn't look a day over 20, when she was first discovered. Maybe she and hubby David Bowie hold the key to the fountain of youth? He doesn't exactly look his 67 years either.
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Can you believe Washington will hit the big 6-0 on Dec. 28?
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How old do you think Walker, Texas Ranger is? Maybe mid-50s? Well, here's a Chuck Norris Fact for you: He turned 74 on March 10.
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It's been 48 years since Welch donned that iconic animal skin bikini in One Million Years B.C., but we'll bet anyone that she'd still look hot in it and that you'll never guess how old she's turning on Sept. 5. The answer: 74!
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Boldly aging in a way no man, or at least very few, have aged before, Shatner looks like he just qualified for his AARP card, but he will actually turned 83 on March 22.
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Forget Inside the Actors Studio! We want the inside scoop on how Lipton looks at most 60 when he will in fact be 88 (!) on Sept. 19.