I've changed my mind about 3 times reading through the comments. But I also have a question. OP, you said you made nice gifts for "their firstborns". Do the daughters each have one child, or has there been another? If so, did you give anything homemade for a second child? If not, would you plan to make something for any new kids?
I'm asking because if this is about giving a homemade gift just to the firstborn, I'd suck it up, forget the rudeness of them not thanking you, and make something. However, if you've set a pattern with the others, or plan to, it might make more sense to opt out of that now. I wouldn't want to set myself up to keep going through this for people who wouldn't use the items or don't appreciate them. And I'm sure you could find something nice they'd use, like an engraved spoon, etc.