I have a 3 1/2 month old GSD puppy that is fine with people touching him or his food while he is eating. He doesn't growl or stiffen up if you touch him or his face, he doesn't care what you do, but will go after our other dog if he gets too close while he is eating. He is fine with his toys just not food. Is that normal for dogs, should I just keep them separate while eating? or is there something that should be corrected?