Hi C., I'm not a dog trainer or specialist, but I do volunteer extensively with a rescue organization and have sent 2 dogs through month long training programs at a spectacular facility in Chicago called K9 University. When your dogs go through training there they require you to read a book called "Leader of The Pack" - a fantastically helpful book that helps the owner understand how and why their dogs behave the way they do. Your dog doesn't growl at you when you're near her food bowl because she understands that you are the Alpha in the house. However, she sees your son as another pup and probably views herself as an equal to your son. In a pack, that means they would eat at the same time, and have to fight a little to make sure they got as much food as they needed....translated to a domestic dog, that means she thinks your son might be trying to get some of that food for himself! Food is the number one trigger for any dog to become aggressive - I completely circumvented this problem at my house my puuting the dogs food bowl in the laundry room and making it the one room in the house my son isn't allowed to go into (I also keep the kitty litter box in there too). We've reinforced this with him since he first learned to crawl and he's awesome about sticking to it. If there's any way you can do something similar, I'd highly recommend it. The bottom line is that any dog, even the most loving & sweet, can be provoked to biting and children can get them there pretty quickly albeit unintentionally. As far as the growling when your son falls on her or grabs fists of fur....my son did this too. My best advice on this issue is to buy the book "Pat Them Gently" and read it to your son a few times a day, while demonstrating how to give your dog "nice pets". We made such a big deal when our son pet our dog nicely, or when he hugged her, that he started doing it purposefully and often just to hear the collective "Awwwwww" in the room. A professional trainer would say to never leave your son unattended with a dog....as a mom, I know the impossibility of that advice. There are always moments where you have to turn your back or walk a few steps away or direct your attention elsewhere. My advice would be to either get your dog or your son to follow you when that has to happen. My dog follows me everywhere, so luckily I never have the problem of her being with my son alone. Hope this helps! have a great day...