I'm having a problem with my 1 1/2 year old. He's getting up between 2 & 3 am every night. This has been going on for months and I'm now at a point where I will try anything. I've tried the warm milk, I've tried just letting him cry, but that turns into an hour of screaming and wakes up my 3 year old, I've tried rocking him but as soon as I lay him down he's up sceaming. What do I do to get him to sleep all night long, any advice????