Hi, M.! Congratulations on your new baby! Your sons reaction to his new brother is so normal and common. My oldest son did the exact same thing with my second son. He's not really trying to hurt him, just letting him know--yes, already--that he's the Alpha, the one in charge. And of course a little jealousy plays into all that, as well. My advice to you would be to involve your older son in EVERYTHING you possibly can with the baby...changing diapers, bathing, feeding, whatever. Commend him on his help EVERY chance you get so that he really feels helpful and involved, not forgotten, in this new addition to the family. The more possitive feelings you can create about the new baby and family make-up, the better. Discipline him, too, as you feel really necessary or if you really feel he could harm your baby, but I would say try to avoid negative feelings as much as possible. Remember, that little newborn is much tougher than we all have a tendancy to believe. Your sons are going to be the best friends either of them could ever have, and you just can't imagine what a blessing (and how much fun) that will be to you and your family. Good luck! You're a great mom!