Young Sheldon's Iain Armitage Looks So Grown Up We Hardly Recognize Him

If you remember the boy genius Sheldon Cooper from "Young Sheldon" with a bowtie, short-sleeved button-down, standing around 4 feet, 11 inches tall, then you might want to sit down, because actor Iain Armitage has undergone a stunning transformation. Armitage was the perfect choice to act out the early days of "The Big Bang Theory" mainstay Sheldon Cooper — you might have even recognized him as the young Ziggy in "Big Little Lies." However, as of late, Armitage is looking less like a science prodigy and more like Hollywood's biggest and swaggiest up-and-comer.

The actor looks effortlessly cool in photos on social media. In May 2025, Armitage posted a mid-meal pic on Instagram that had fans going wild. His casual outfit, paired with ornate jewelry and perfectly coiffed hair, was a far cry from his nerdy "Young Sheldon" costume. "Sheldon cool version," someone commented on the post. "Can't believe how much you have grown," another wrote in awe. "In my memory you are still a little boy in Young Sheldon who have not even had full of your teeth [sic]."

One other user was convinced he's the doppelganger of another famous actor, writing: "Anyone notices [sic] the resemblance to Tom Cruise?" The blue eyes, the brows — we totally see it.

Since "Young Sheldon" concluded its final season in 2024, Iain Armitage hasn't been hasty with jumping back on TV. From what it looks like, the star has been hanging with family, and even a few A-listers. In May 2025, Armitage posted a photo with Jane Krakowski and Jesse Tyler Ferguson on Instagram, after they all seemingly attended the Broadway musical "Here We Are." In his caption, Armitage wrote "#modernsheldon" and "#youngfamily" as a nod to the shows that made him and Ferguson famous — Ferguson made his staggering fortune on "Modern Family."

Armitage also appears to have traded in his signature Sheldon Cooper bowtie for a sophisticated maroon tie and grey suit while advocating for the arts in front of Congress. The "Big Little Lies" actor posted on Instagram about his mission with The Creative Coalition — a nonprofit charity consisting of members from the arts and entertainment industry — in April 2025, writing: "We were invited into the offices of Congressional reps on both sides of the aisle and we got to explain why we believe that arts funding is vital in every congressional district."

But when he's not filling his time with philanthropic pursuits, Armitage is trying new things. In October 2024, he revealed to People that he has picked up a hobby in aviation. "I just got my pilot's license, or my student pilot's license," he said, adding, "I hopefully will get my private [pilot's license] when I'm 17." In July 2024, he shared on Instagram that he had completed his first solo flight piloting the plane, writing: "This was one of the very best days of my life!!"