Hello Rose, and welcome to the Disney Parks Moms Panel! Thank you so much for bringing your question to us.
I think the best quick-service restaurant option in the Magic Kingdom Park for your family is
Columbia Harbour House. They have been reeling in my family for years with some pretty tasty battered fish, grilled salmon, lobster roll, and New England clam chowder. If you enjoy tuna, their Anchors Aweigh Sandwich is one of my must-have lunches in the park. For kids, you will notice on their
menu a chicken nuggets and fish platter. I spoke with a Cast Member this morning and she assured me that you can modify this menu item to only include fish. When ordering, just let the Cast Member know of your dietary needs and they will be happy to prepare you a seaworthy platter.
I hope you have a great lunch when you drop anchor at Columbia Harbour House. Feel free to come back and visit us with any other questions you may have.
Brandy