The character or the actor? Brick Heck, age 11, is played by 13 year old Atticus Schaffer. FYI Brick Heck has a form of Aspergers Syndrome while in real life Atticus Schaffer suffers from osteogenesis imperfecta or 'brittle bone disease' type one.
(Sue Heck, age 13, is played by 20 year old Eden Sher and Axl Heck, age 16, is played by 21 year old Charlie McDermott.)
On the show the middle, brick is eleven years old. He is the youngest child of Frankie and Mike Heck and they live in Action, California with his family. He is known both in the household and for his odd behavior.