There are several reasons for children to have convulsions after crying: 1. Most of them are related to their own diseases, such as the child’s congenital or acquired stunted development, lack of trace elements and vitamins in the body; or the child’s brain suffers from certain disorders, such as insufficient oxygen supply caused by cerebral vascular stenosis, epilepsy with abnormal brain nerve discharges after excitement, etc. These diseases can trigger the symptoms of convulsions when the child cries; 2. A part of the baby will appear convulsions when crying very hard, which is a normal physiological phenomenon called anger spasms, and the symptom will be relieved as long as the parents calm the baby in time; 3. It may also be an abnormal behavior of respiratory movement disorder in infancy and early childhood, and because the child can easily show symptoms of hyperventilation or respiratory arrest when crying and throwing tantrums, it will lead to limb twitching occurs.