Update: More corrections and additions.
This is kind of spoilery, so if you haven’t read the archive (lately?), you might want to do that first.
I don’t know if this will help, but I put a chart together showing family relations. It’s not complete. Rocky’s father had several brothers. Blank bubbles are people that I haven’t named, or don’t quite recall. There’s also a few relationships that haven’t been mentioned yet. Etc…