It’s important to understand what is realistic to expect for night sleeping and sorry to have to tell you this, it isn’t 12 consecutive hours of sleep. Let’s look at baby sleep expectations and the amount of sleep for infants at various ages.
A baby’s biological clock takes time to mature and does not work smoothly until she is four to five months. This same baby has an immature metabolism as well, and can’t go without nourishment throughout a long night. Baby sleep expectations needs to be adjusted throughout her first years of life.
A baby younger than four months old usually sleeps between each feeding, which during the day is about every three hours, and during the night may start to stretch to four or five hours between one or two of the night feedings that averages to around 16 hours per 24 hours period.
Around 4 ½ months old, a baby starts to consolidate naps and has two to three naps per day. They needs 14–15 hours of sleep per 24-hours and gets that in his 2-3 naps and a night sleep of about 10 ½ hours, usually with one dream feed.
Around nine months old, a baby’s sleep periods will come together and her biological clock is more mature, so that she wakes up and goes to sleep at about the same times every day. She will be taking two long naps a day, and sleeping at night for about 10½ hours, for a total of 13-15 hours of sleep per 24-hours.
Between 13 and 24 months old, the child will have one long nap and 10½ hours during the night to get about 13-14 hours of sleep per 24-hour day.
Of course, all babies are different and there are always a few on either end of the continuum who need more or less than the guideline says. To help your baby sleep longer and get the amount of sleep she needs read my article on baby sleep cycles at