Eight-month-old baby teasing him when the jerk is generally a normal developmental phenomenon, if the jerk when the baby appears to fart more, crying and other phenomena, it may be indigestion or abdominal distension caused by a cold abdomen. Eight-month-old babies are particularly interested in the outside world as their bodies slowly develop and their mobility gradually increases. When parents interact with them, they will show excitement and may have jerking movements. Eight-month-old babies may also jerk when teased because of abdominal discomfort, especially if they have indigestion that leads to bloating. This is especially true if the baby has indigestion which leads to bloating. The baby will also expel gas from the abdomen and fart more often. When the baby catches a cold, it can also cause indigestion and abdominal distension, which in turn leads to the phenomenon of tic-tac-toe. Parents can massage the abdomen of the child to relieve the child’s abdominal pain. In addition to the above reasons, calcium deficiency and lumbar muscle injuries may also lead to frequent jerking of the baby. If the baby in addition to jerking, accompanied by crying, waist redness, swelling or lumbar weakness and other phenomena, should go to the hospital for timely examination and treatment.