It can depend a lot on if your baby is a breat or bottle boy. My son is 7 months old and has only been sleeping through for about a month, although some night are bad. He used to wake once during the night anywhere between 4 and 6 for a feed then all of a sudden he started going until about 8am. Maybe once he starts solids he might sleep longer (don't start them early just to cure this).
My husband works with a guy whose 19month old still doesn't sleep through, but they tell me girls aren't good sleepers. Thats what I've been told though, I can't offer experience on that one.
Hope this has been of some help to you and when you least expect it your son will just start missing the early feed. We tried giving Liam water or dummy so he wouldn't think it was worth it waking for a feed but this didn't work as it only settled him for about an hour, so I figured I was up in the first place I might as well feed him then.
Take care and good luck.
member since 2004