Iain Rupert Armitage (born July 15, 2008) is an American child actor and theater critic. He is best known for his starring roles as Sheldon Cooper in Young Sheldon, spin-off of The Big Bang Theory, and Ziggy Chapman in Big Little Lies. In 2018, he received the Young Artist Award for Best Performance in a TV Series - Leading Young Actor for his role as Sheldon Cooper. He also voiced young Shaggy Rogers in Scoob!.
On Nickelodeon, he guest stared as himself on Unfiltered and Group Chat with Jayden & Brent, and voiced Chase in PAW Patrol: The Movie in place of Justin Kelly.