Why is the baby\’s lower lip shaking? Is it normal?

Question 1: My baby is four months old. His lower lip suddenly trembles, as if he is frightened or cold and out of control. It happens twice, lasting 1-2 seconds, with an interval of more than ten seconds. Is this normal? Other than that, there are no other abnormalities. Dr. Wang Yanli answered: Cold, this happens occasionally before urinating, and lack of vitamin D and poor calcium absorption, which causes vitamin D deficiency tetany and high-frequency mandibular shaking. Vitamin D supplementation is required starting two weeks after birth. , and get more sun at the same time. Question 2: The baby was born at 29 weeks. He is now four and a half months old, and the corrected gestational age is more than two months. Is it normal that he sometimes blows bubbles in the past two days? When he is hugged vertically, his head will be tilted very far back. Is this normal? Dr. Zhang Yanmei’s answer: It doesn’t matter if your breathing is steady, no snoring, no coughing, and occasional bubbles. When you tilt your head back, pay attention to high muscle tone, and you need to go to the pediatric care department of the hospital to have your neurological development evaluated. Question 3: My child received vaccinations in his left arm when he was born. It’s been almost a month. Is it normal for this picture to appear? Dr. Cui Lixia answered: The left arm was vaccinated with BCG vaccine after birth. This reaction is normal. If the pus comes out, you can apply iodophor, and the scab will usually form in 2-3 months.