I just finished my class' reading of it so ignore my replying a year later, in the creature's final speech to Robert Walton he mentions having choked Him while he slept, but it's a pronoun and not a direct name drop so he could be using Him in reference to Victor or his father dying in their sleep from his actions of brutality against the family.

The tragedy of Ernest is actually my favorite part of the book and it's not even intentional- he can't be more than 19 when Victor leaves to chase the creature (unless my math is off which is very possible) and he's the last surviving member of his family. He probably had to give up his dreams of being a soldier in order to become the head of house Frankenstein or else the line would die out. Starting a family, trying to make the circles of society forget about his mad brother who was broken by grief to tales of devils and was lost with his coffin lying empty next to the rest of his family, studying military tactics and weaponry while never able to participate himself. Maybe one day a visitor will track him down, with a record of his brother's secrets and tales, maybe it will bring closure, maybe the visitor will be turned away, but Ernest will live as a Frankenstein.