"Young Sheldon" debuts on CBS on Sept. 25, 2017. Iain Armitage stars as the title character on the sitcom, which is a prequel to "The Big Bang Theory" and centers around the childhood of Jim Parson's character, Sheldon Cooper. In honor of the show and its pint-sized star, Wonderwall.com is taking a look back at more of our all-time favorite child actors of the small screen. Keep reading to relive their glory days…
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Mary-Kate Olsen and Ashley Olsen were just babies when they first shared the role of Michelle Tanner on "Full House." They played the part, which launched them to international superstardom, from 1987 to 1995.
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Keshia Knight Pulliam became the youngest Emmy nominee ever (a record she still holds) in 1986 when she was recognized for her performance as Rudy Huxtable on "The Cosby Show," a part she played from 1984 to 1992.
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Millie Bobby Brown has only been on our radar since the first season of "Stranger Things" debuted in 2016, but we're already confident that the British actress who plays Eleven will go down in history as one of our all-time favorite child stars. (She's only 13 but she's already one of the youngest Emmy nominees in history thanks to her work on the Netflix series.)
Don't make us choose just one! We loved every member of the titular family on "The Brady Bunch," which aired from 1969 to 1974. Susan Olsen, Maureen McCormick and Eve Plumb starred as the three "very lovely girls" on the show, while Christopher Knight, Barry Williams and Michael Lookinland portrayed their stepbrothers.
Fred Savage was just 13 years old when he earned an Emmy nomination for his work as Kevin Arnold on "The Wonder Years," on which he starred from 1988 to 1993 opposite the adorable Danica McKellar as Winnie Cooper.
Though he never earned an Emmy nomination for his work as Cory Matthews on "Boy Meets World," Fred Savage's little brother, Ben Savage, deserves some credit for the sitcom, which aired from 1993 to 2000.
The kids of "Modern Family" have grown up before our very eyes! When the sitcom debuted in 2009, Rico Rodriguez, Nolan Gould, Ariel Winter and Sarah Hyland were just tiny little things. Now the youngest of the group, Nolan, is just a few weeks shy of his 19th birthday!
Soleil Moon Frye shot straight from the TV screen into our hearts when she starred as Punky Brewster on the eponymous sitcom from 1984 to 1988.
Though she's now a bona fide movie star, Kiernan Shipka launched her career on "Mad Men." The super-chic teen starred as Sally Draper from 2007 to 2015.
Before he was one of Hollywood's hottest directors or the young star of "Happy Days," Ron Howard was a child actor on "The Andy Griffith Show." He starred as Opie Taylor from 1960 to 1968.
Though things for Frankie Muniz have been a bit rocky in recent years, we'll always love him for starring as the title character on "Malcolm in the Middle" from 2000 to 2006. He even earned an Emmy nomination for his work on the show back in 2001!
After starring as Patricia Apple on "Apple's Way" from 1974 to 1975, Kristy McNichol went on to play Letitia "Buddy" Lawrence on "Family" from 1976 to 1980. She won two Emmys and earned two more nominations for her work on the drama.
"Game of Thrones" has become an undeniable force in pop culture since its 2011 debut, and while there are many characters we've loved and lost over the course of its seven seasons on HBO, there's none we've loved more than Arya Stark. Maisie Williams had just turned 14 years old when she made her acting debut in the role.
During the '90s, there was no time quite like "Tool Time" — thanks in part to Taran Noah Smith, Jonathan Taylor Thomas and Zachery Ty Bryan, who starred as the Taylor brothers on "Home Improvement" from 1991 to 1999.
Alyssa Milano was just 12 years old when "Who's the Boss?" debuted. She starred as Samantha Micelli on the sitcom from 1984 to 1992.
The adorable Ricky Schroder starred as Ricky Stratton on "Silver Spoons" from 1982 to 1987.
The incredibly cute and super-stylish Miles Brown has been starring as Jack Johnson on "Black-ish" since 2014, when he was just 8 years old. Too cute!
Four little girls charmed their ways into our hearts on "Little House on the Prairie," which aired from 1974 to 1983. Twins Lindsay and Sidney Greenbush shared the role of Carrie Ingalls, while Melissa Sue Anderson portrayed Mary Ingalls and Melissa Gilbert starred as writer Laura Ingalls.
Danny Pintauro starred as towheaded cutie Jonathan Bower on "Who's the Boss?" from 1984 to 1992.
Maddie Ziegler was just 9 years old when she debuted on the reality TV show "Dance Moms" in 2011.
Though there were many young stars on "The Partridge Family," none were more beloved than Danny Bonaduce, who starred as Danny Partridge from 1970 to 1974. (David Cassidy was 20 when the show debuted, but Danny was just 11.)