Well, to answer their question, babies sleep for around 16 to 17 hrs (or even more) per day. We are talking about newborns. Sometimes they sleep for 3 to 4 hrs at a stretch or some other time they might just get up within 2 hrs. They get up because they need to be fed and then they sleep again. As infants, they do not understand the difference between day and night. So do not expect your child to not disturb you at night.
However, the sleep pattern changes as the baby grows. Gradually, your baby will adapt the lifestyle of the world beyond the womb. Slowly, they become more playful and active during the day. So they start sleeping more at night as compared to the newborn. Now is the time when every parent should make a proper sleeping schedule for them. It helps a lot in the long run