Newborns usually sleep more than 20 hours a day, so as long as the baby is in good spirits and eats milk well, there is no need to worry. If the baby does not eat milk well after waking up and is also in poor spirits, you cannot rule out that there is a disease, see if the baby has a stuffy nose, runny nose or cough, and if necessary, go to the hospital and let the doctor hear the case. Another situation is that the baby’s sleep time is relatively short, can not be ruled out with vitamin D deficiency, because the lack of vitamin D easily lead to easy to panic, irritable, difficult to sleep, after giving vitamin D supplementation, most of them can be relieved. Therefore, the exact length of sleep is not the same for each child, but most normal babies should be around 20 hours or so.