The young actor will play Carter Grant, the son of Calista Flockhart‘s character Cat Grant. Grant is the boss of Melissa Benoist‘s Kara Zor-el, Superman’s cousin who becomes the superhero known as Supergirl.
Twelve-year-old Carter is described as sensitive and shy, and harboring a crush on Supergirl, which he confesses to his babysitter Kara. Miller is set to make his debut in Episode 4.
On the drama, Chyler Leigh plays Alex Danvers, Kara’s older foster sister and David Harewood stars as Hank Henshaw, a former CIA agent and now the head of Department of Extra-Normal Operations.
Others cast in the series include Mehcad Brooks as James Olsen, “Nashville” alum Laura Benanti as Supergirl’s birth mother and former Superman and Supergirl Dean Cain and Helen Slater, respectively, in mystery roles.
Greg Berlanti and Ali Adler are writing the one-hour drama, and also executive producing, along with Sarah Schecter and Andrew Kreisberg. Berlanti also serves as producer of “Pan.”