LB is nearly 9 months old and has never, ever slept through. Well, if you count 5 hours as sleeping through (see Pantley) he has managed it about 6 times. Usually he wakes up every couple of hours or less. We have had blessed periods where he has slept for 3 hours at a time but it’s been a while. Despite this, he is perfectly happy and healthy. It’s just that his parents are zombies much of the time.