Aaron Heffernan

Heffernan grew up in Dublin, Ireland. His father, David, is a radio producer and his mother Tina is a model. He is of Dominican descent through his mother.^{[5][better source needed]} Heffernan has two older brothers: Simon, a personal trainer and online coach, and Jesse, a hip hop artist.^[6] His first cousin is model Thalia Heffernan.^[3][7]

He studied drama and classics at Trinity College Dublin.

In 2012, he co-founded the Collapsing Horse Theatre Company with fellow student and actor Jack Gleeson.^{[8][9][10][11][12]}