B.B.
Although my kids are all farther apart, I can tell you some things that may help.
#1. When he comes to meet baby after baby arrives. Make sure you are not holding baby...That leaves your lap open for him and someone else should introduce them... (My boy wouldn't even sit on my lap at the hospital... Weird place and weird clothes. He would only go to his uncle that was spending the day with him aka baby sitting. Don't force it.)
#2. When you go home. Someone else carry baby... That leaves your arms open to grab him in big hugs.
#3. Get him a baby doll. (I know his daddy may say something about that, but I found with our #2 (first boy, ) he'd find one of his big sisters dollys and "pretend he was taking care of it" when I had #3 in arms. Buy a fake baby bottle the kind with the dissappearing liquid stuff to go with the baby. Give him a diaper to put on the baby doll. Teach him to treat the baby as you do YOUR baby... NO hitting it. NO throwing it... etc. Do not be suprized if you are nursing to find him with the dolly under his shirt. Its how kids play. They copy what they see. I always told my boy while I nursed baby, that some babys drink mommy milk, some drink from a bottle...
#4. I agree with not leaving them in a room alone. I set up several different places in the house that I had out fits for both, diapers, wipes, etc. That way no matter where I was if I needed to, I could change baby, or big brother without having to traipse up and down stairs... (also a saver in the first few weeks after delivery)
#5. Make sure you devote one on one time with big brother. A lot of issues are because of a feeling of lacking the attention.
#6, DO NOT CALL HIM YOUR BABY ANYMORE!!! Only refer to him as a BIG BROTHER, Big boy, Little man, etc. Start before the baby comes out. If he agrees, I'm the big boy, thats the baby, there won't be as much tug of war.
#7. Get him a couple new things. But don't give them to him yet... Wait till his baby comes home and give him a present from the baby... That gives him something to do while you feed the baby. Pop out a new " big boy "toy every couple days for the first week or so till he gets accustom to you having to sit down WITHOUT him on your lap. Keeps his mind and hands busy for at least a few minutes...
GOOD LUCK!!!! And congrats!!!