Samira woke up with a weird rash covering her one arm. Googled it and found the exact thing with…

Samira woke up with a weird rash covering her one arm. Googled it and found the exact thing with pictures and descriptions: hives. But, I don't know what caused them. She didn't eat or drink anything unusual last night, she hasn't been introduced to anything new, detergents didn't change, etc...but she's got hives. They're not bothering her right now...it's just bothering me. Lol.