So today I gave Bubba (7 months) and Bonnie (4 months) their Kong filled with peanut butter. I walked away for a few minutes and next thing I hear alot of growling and snapping. I ran over to their play area and realize Bubba is being really protective over his Kong, Bonnie was really confused and Bubba was just snarling at her. So I came over there and stopped it, immediately Bubba backed away and went back to being normal. I sure don't want this behavior with him, what is the best way for me to nip this in the bud?