Thirty, flirty and thriving! It may be hard to believe, but it's officially been more than 17 years since 13 Going on 30 first hit theaters on April 23, 2004. Yes, that means if Jennifer Garner's Jenna Rink were 13 the day the movie premiered, she would be 30 years old today.

And while we obviously know that Garner, Mark Ruffalo and Judy Greer have gone on to A-list careers as, respectively, America's sweetheart, an Avenger and the BFF in basically every romantic comedy known to mankind, we got to thinking about what the child actors who played the younger versions of their characters are up to these days.

Read on for a catch-up on the lives and careers of Christa B. Allen, Sean Marquette and Alexandra Kyle. Wanna see their IDs? We totally have 'em!

Christa B. Allen (Young Jenna Rink)

A then-11-year-old Christa B. Allen landed the first major film role of her career playing the younger version of Garner's Jenna, whose magical birthday wish kicks off the entire plot of the beloved rom-com.

Half a decade after 13 Going on 30, the young actress reunited with Garner to once again play the younger version of her character in 2009's Ghosts of Girlfriends Past. From 2011 to 2015, she had a main role on ABC drama Revenge, playing spoiled teen socialite and Hamptons royalty Charlotte Grayson for four seasons opposite Emily Van Camp, Madeleine Stowe, Gabriel Mann, Josh Bowman, Henry Czerny and Connor Paolo.

This year Allen rings in her own 30th birthday, and marked the occasion by penning a special essay for Yahoo! that looked back on the role that launched her career. "It was playing 13-year-old Jenna Rink in 13 Going on 30 that played such a dominant role in my actual life. I could have never predicted how she would come to follow me forever," she wrote. "Because of that role, I have such a personal connection with anyone who was touched by the film. I feel invisibly bound to people turning 13, 30 and everyone in between."

Oh, and last Halloween, she also recreated Jenna's birthday look in *that* famous birthday dress. The TikTok went, well, totally viral.

Sean Marquette (Young Matty Flamhaff)

It's safe to say Jenna's wish would've been nothing more than just a wish if it hadn't been for the dollhouse and magical wishing dust gifted to her by her nerdy BFF Matty Flamhaff, who was played by Sean Marquette.

Ahead of 13 Going on 30, Marquette had already clinched a regular role on soap opera All My Children, as well as guest spots on everything from Lizzie McGuire and Rocket Power to Without a Trace.

In the years since his character sprinkled wishing dust on the roof of a dollhouse, Marquette has continued steadily acting, and today is best known for his recurring role as Johnny Atkins on ABC's The Goldbergs and its 2019 spin-off Schooled. He also has numerous voice acting credits to his name, including as Mac on the now-classic Cartoon Network series Foster's Home for Imaginary Friends.

Alexandra Kyle (Young Tom-Tom Wyman)

Was there anything more intimidating that the Six Chicks? As the most popular girls in school, the clique lorded over poor Jenna's life and humiliated her on her 13th birthday — led by Alexandra Kyle's Tom-Tom Wyman, of course.

But Kyle's career dated all the way back to the mid '90s by the time she appeared in 13 Going on 30, having starred opposite Kiefer Sutherland in two different thrillers in 1996 alone: Eye for an Eye (with Sally Field) and A Time to Kill (with Sandra Bullock, Samuel L. Jackson, Matthew McConaughey, Ashley Judd and Kevin Spacey).

13 Going on 30 turned out to be the young star's penultimate film role, as she pivoted to TV work following 2004's Funky Monkey. Kyle eventually racked up recurring parts on Without a Trace, Days of Our Lives and Justified, followed by one-off guest spots on NCIS, Rosewood and the short-lived MTV series Mary + Jane.

In  2020, she also duetted with Allen on a viral TikTok inspired by their epic 13 Going on 30 costumes, writing, "TOMTOM AND JENNA FOREVER."

Popular Child Stars From Every Year

Below, Stacker sifted through movie databases, film histories, celebrity biographies and digital archives to compile this list of popular pint-sized actors from 1919 through 2021.