Thanks for answering all my nosy questions... you never know what might come out of it. Your baby sounds like he's doing really, really well... except for this sleep thing!
Sophia's ideas sounds good. Another suggestion might be to give him some more to eat... more solid food... either with his dinner or with his evening snack. Maybe he's waking and he's a little bit hungry because he's growing so well. I know there are good suggestions somewhere about what foods are sleep-inducing. Right now, all I can think of is pasta,

and that's probably not right for him.
For the white noise I'd suggest a softly playing radio on the local classical music station -- (less voices, more music), and it should be so quiet that you have to be absolutely still to hear it.
The wet diapers... those could be waking him up now that he's getting older and more aware. If you could use the disposable kind at night that take the moisture away from his skin... maybe that would help. Some babies will start to stay dry through the night.
The other thing I'd suggest is to discuss it with him. OK, yeah, he's a baby, but babies understand far more and lots sooner than they can speak. In only the kindest terms tell him that you need your sleep and you'd like for him to ..... (It's the power of suggestion and it couldn't hurt!)
Let us know how things work out. We're rooting for you and your baby. It is so hard (so horribly hard) to feel great if you can't get your own sleep. Best wishes!
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