So my coworker's last day was yesterday (nothing to do with Roe v. Wade just pure coincidence). Him and I are very efficient at our job and communicate really well, so well that it has been noted by our superiors. He is being replaced by someone else at our company instead of a new hire. The problem is that my new coworker is over twice my age (I'm 24 and they're in their mid 50s) and a large chunk of our job involves using computer software which he is not efficient with. I can understand some of it, he's still training and not everyone is familiar with certain types of software, even people my age. Because of this I'm responsible for picking up the slack while taking time out of doing my job to attend to every question he has. I think I'll be alright but it's going to suck until he hopefully gets up to speed which is going to take months.
I thought to myself: “Wouldn't they be absolutely screwed if I left?” Bam. Leverage for a raise. I just recently got a raise too albeit not even 50 cents. This left me feeling less than stellar considering how fucked inflation is. I'm the backbone of my department right now and I'm unsure if they could afford to lose me. So I want more than mere spare change an hour. I'm at $16.30/hr and I want to demand like $20/hr. If they're not hiring anyone new then shouldn't I be fairly compensated for having to take on the workload of more than 1 person?
I would love advice as to how to go about this. I have a lot of respect for my manager because he treats all of us like actual human beings. I'm not sure if I'd quit over not getting raise and I don't want to outright threaten to leave. Buuuuuut I do want to convey that I would perhaps move on if not properly compensated.