How could you forget the adorable face of Malcolm in the Middle's Dewey? Erik Per Sullivan played the sweet younger brother of Malcolm, and he did an amazing job - everybody loved him. Sullivan remained on the show for the entire seven years that it ran, between 2000 and 2006. We still think he's super cute, but we don't know if we'd recognize him on the street!
Since his days on Malcolm in the Middle, Sullivan hasn't done a whole lot of acting. He ended up going to college and he has done a few things here and there, but ultimately, he didn't make it as an adult actor. One cool thing he did get to do was be the voice of Sheldon in Finding Nemo - he's the sweet little seahorse that goes to school with Nemo.