Is this selfish of me?

My mom & sister is depending on me to help them move into a new place in a month.

I have a 4 year old and my sister is pregnant. My mom works but my sister doesn’t.

We all kind of stay in 1 bed room apartment rn. I had almost 1k saved but due to my sister losing her job I had to pick up the slack.

I don’t want to go through this again but my sister watches my son for a few hours of the day 4 at max. So I feel like I need to help them. I’ve been on my own before. I’m just tired of going through this.

What would y’all do? Help or try to branch off. I’m trying to get my son in school so I don’t have to worry about a sitter.