Most Disney restaurants can accommodate food allergies. Make sure you note your sister's peanut allergy on your ADRs. If you make them online, click Special Requests and tick off food allergies/intolerances for your party. Also, let the server know. It should be noted on your ADR, but sometimes they forget to check. We ate at Ohana several years ago with 2 peanut allergic kids. We requested no peanut sauce at our table. The bread, dessert and one of the sides (I think noodles) were unsafe, so they got mac and cheese kids meals and enormous bowls of vanilla ice cream instead of the regular food. At QS locations, tell the order taker about the allergy. They have ingredient info and can let you know what's o.k.