My daughter has small red bubble underneath the tongue. what should we do?

Leave it alone: Sounds like a little fluid filled cyst. Just leave it alone, it will drain on its own. As long as there is no fever or overlying redness or tenderness, this will take care of itself.

Start w pediatrician: Without seeing a picture, cannot provide an accurate diagnosis. If there is any pain, difficulty breathing, or concerns you immediately, see an urgent care or ER. Otherwise, make an appointment with your pediatrician to go over the complete history and perform an examination. Then a diagnosis can be given and treatment plan if needed.