S.G.
My twins have sleep issues too. They are 3 and one still wakes up druing the nite every 3-4 hours. What happens is that she doesn't enough during the day, so she's waking up hungry at nite. She is a picky eater which doesn't help the situation. I try giving her pasta and bread at nite, which does help sometimes. But situations like that can really drive you batty. If I know she didn't eat enough through out the day, I give her a bottle of pediasure at nite. If were having a bad nite, I put melantonin in her bottle. The liquid form about 1tsp or 5ml. Ask your peds if you can give her melatonin its natural and doesn't damage kids, make sure you get the liquid form without alcohol. You can buy at any food health store. The liquid form is easier to hide in juices. The melatonin has truly helped my situation. You might also try omitting the naps. Thats what I have to do with my daughter now. This way she is tried and more likely to sleep thru the nite.
hope the info helps