Don't think it's ever been said, but I would assume they would have come from either Olivia, or the Chipette's parents before they wound up with Olivia. There is sadly not alot of info on the girls, as they feature in very few episodes.
That is if you're talking the 80s series, if you mean the live action/cgi movies, probabily their parents, although once again it's not been said.
They're on about the LA films yes. The said Simon didn't have his before they met Dave. As for Jeanette as you correctly said we don't really know. It would have made more sense though of she didn't already have them and Ian gave them to her.