A newborn baby’s smile is a normal physiological phenomenon, which is only an instinctive response of the baby or a subconscious smile.
Newborn babies with high nervous excitability, easy to induce a strong physiological reflex action, there will be a body tremor, shaking, sudden rapid facial twitching, or involuntary physical activity and hand and foot dancing and other uncontrolled movement performance, so the newborn baby smile can also be considered as a manifestation of facial tremor.
At the same time, the newborn baby, has a congenital emotional responsiveness, will appear pleasant, painful and other expressions, and physiological needs to be satisfied or not have a close relationship. Therefore, a newborn baby’s smile is a normal phenomenon that does not need to be dealt with.