‘Designated Survivor’: Meet the Cast of ABC’s New TV Show

Tanner Buchanan as Leo Kirkman

17-year-old Tanner Buchanan as been cast as the 16-year-old son of Tom and Alex Kirkman. According to The Wrap, "[Leo] is... rebellious and self-absorbed but steps up to the plate when he needs to comfort his little sister..." The actor has appeared as a guest star on shows like Grey's Anatomy, Major Crimes, and The Goldbergs. He was also cast as a series regular in Disney Channel's Girl Meets World. (Instagram/teentvconfessions)