Sonic Drive-In

My granddaughter ordered a milkshake in a door dash order. She has rather severe peanut allergies but didn't think a plain milkshake would be a problem. However, shortly after drinking it, her face and throat began to itch. Thankfully, she was able to take some remedy meds to counteract it. I think that this is terrible that one cannot expect to order something without getting cross contamination. Seems like it's a cleanliness/sanitation issue.