You can encourage this with dark room at night and sunlight during the day. On average by14 to 18 weeks your baby should be starting to get a sleep routine which is more of the deep sleep they require. If you are fortunate and tried early to establish a sleep pattern most of these sleep hours will be at night and early afternoon. You can try to establish a pattern of afternoon naps and early night bedtime. Now we are at 24 weeks its time for all night sleep for you.
Sleep patterns are different and some fortunate parents have already enjoyed all night sleep.
Its time ,with a healthy child, to let them stay in the crib. Studies have shown most babies wake through the night. The difference is some are quiet, look around for awhile then go back to sleep. Others are a little more active and vocal and some are the screamers , they are just more vocal. This is the time to let them be vocal for awhile they will go back to sleep.