One of my friends tells a story when she was 8, and she was deathly allergic to nuts. She was at a friend's birthday party, and was given a cookie. She went to her mom to ask if it was okay, and her mom asked the mother of the birthday girl, "Does this have nuts in it? My daughter is deathly allergic to nuts." The woman said, "No." So she was allowed to eat the cookie. A few minutes later, her face started to swell, her throat started to close, and she started having a deadly reaction. The mother freaked out, and said to the other mom, "I thought you said there was no nuts in these?" "I mean, there are just one or two walnuts, but they are ground up so fine, she couldn't have tasted them." My friend had to go to the ER.