It may or may not be normal for a 50-day-old baby to sleep through the night, which should be judged specifically based on the baby’s overall condition. A 50-day-old baby is asleep most of the time, except when he is awake and crying when he is hungry, and he goes to sleep soon after nursing. If the baby sleeps all night except nursing, or even sleeps without nursing, as long as the baby is awake and in good spirits and can nurse normally, it is considered normal. If the baby sleeps for a long time and eats less, or is depressed after waking up, or even in a state of lethargy, it is necessary to consider that there is a disease, and it is recommended to go to the hospital for examination. If your baby sleeps for a long time and you are worried about having a disease, take your baby to the hospital in time and let the doctor check his/her health.