Blisters on the tongue in a young child can be a sign of a common childhood infection called herpangina. This is commonly associated with high fevers and pain in the mouth, which sometimes makes it difficult for kids to consume enough liquids. While it is concerning, it will generally resolve quickly without other concerning or long term consequences. While herpangina is a common cause, however, it is not the only cause, and you should have your daughter examined by your doctor
if the blisters have not resolved by the time you are reading this. One way to find out if your daughter's symptom is concerning is to ask about her friends and schoolmates, and determine if any of them have had similar symptoms. If they have, and the symptoms have resolved with no further problems, then that is generally a good sign. If it is herpangina, it tends to be shared among close groups such as school classes and play groups. Good hand hygiene and avoiding sharing cups and utensils will help to decrease the spread. Please speak with your doctor about your daughter's symptoms and have her examined to see if there is more that should be done.