Hi Twindaddy,
I posted the same question when the girls were little.
I too know how you feel, you become obsessed with sleep and wonder if they ever will sleep through. You think that you will have to survive on broken sleep forever. I even got to the point where I was out and about, and every baby I would see, I would wonder how well they slept!!
Well, guess what, it doesn't go on forever! Alicia and Sophie slept through from 5 months and from 8 months respectively. I finally got Sophie sleeping through after I consulted a sleep doctor. (let me know if you want the details. - he also has a book out).
What I learned among other things, is that a learned skill for babies is to get themselves to sleep on their own. That includes waking in the middle of the night (as we do) and getting themselves back to sleep. They said that from 6 months, they have the capability to sleep through without needing to be fed. - except for a 10pmish "rollover feed". That is what we did, we had a sleepy feed at 10pm, then if they woke in the night, rather than feeding, we encouraged them to go back to sleep, by sticking a dummy in, or letting them cry for a bit. After a while, they worked out that it wasn't worth waking up properly if they didn't get anything. It takes a few nights, but is worth the effort. If I did this with Sophie, it didn't wake Alicia, but I know some others have problems with them waking each other. Maybe you could try seperating them until they are sleeping properly.
It might be that when they are waking in the night that it is just out of habit, and they are hard to settle because they are overtired and cranking about being woken up - like we are!
I also agree with the making sure they are nice and warm thing. We were still wrapping them at 8 months too. The sleep doctor also recommended that we ditch that too, becuase if the woke up because they were unwrapped, it was another thing you had to get up for!
I am absolutely NO expert, but just passing on the information. I hope that you get some sleep soon.
Cheers
Kate
Alicia and Sophie 2/12/02