Hi,
My DD is going through the same thing, but it has only been a week since it started, I tried feeding her every two hours instead of 3 but it doesn't seem to help. I think it has something to do with her growth spurt.
She use to eat once a night, at about 5 am, and then sleep till 8am. But now she is waking at 3, 5, 7 and then sleeps till 9.
I think she got use to waking at those times in the night and now does it out of habit. But she still acts as if she needs to eat, she won't resettle till I feed her.And she doesn't even take a full feeding, she only eats for like 5 or 10 minutes, her normal full feeding is about 20.
I have tried cluster feeding starting at about 6 but that doesn't seem to help her sleep longer.
Has your son already gone through his growth spurt?? It could somehow be related