Angel of Death (Situational Irony)
The Young Man is, as the script tells us, the "Angel of Death" who takes Grandma away to her final resting place. Ironically enough, he is a young handsome aspiring actor from Southern California who can barely get his lines out. There is a comic and ironic tension between the fact that the Young Man is such a healthy looking young person—a superficial, wannabe-movie-star—and the fact that his job description is "Angel of Death."
Grandma's Death (Dramatic Irony)
While the literal terms of Grandma's death are unclear, there is a bit of dramatic irony in the staging when the lights come back up and Mommy and Daddy find Grandma half buried in the sandbox. The stage directions tell us that Grandma "plays dead," and Mommy and Daddy believe that she is fully dead. Albee leaves it ambiguous whether Grandma has literally died, but the direction that she is only playing dead would suggest that the audience is privy to something Mommy and Daddy are not.
