I wouldn't be afraid to ask! My 18 yo son, who is very picky, was able to get grilled cheese at every restaurant we ate at in October. It was fun to see the different ways they make it for him -- sometimes a double decker, another time extra cheesy, and another two sandwiches on one plate. Of course the charge was more of an "adult" price but at least he was able to eat. I think they want to be able to make you happy as long, so as long as they have the burger available and it's not super busy, I bet they'll do it. Good luck and let us know how she makes out.