A four-and-a-half-year-old child reported pain on the anterior side of their left thigh, which started two days ago. The pain is felt exactly at the front when lightly pressed, but not when not pressed. While running, the pain is experienced if the child does not lift their toes, but seems to ease when they do. Today, the child has been limping occasionally while walking. We conducted blood tests today, including routine blood tests and six super tests, and the doctor examined and said there were no issues. However, why does the child have leg pain? They do not have a fever or a cold, nor any other symptoms. We are very concerned.