I think getting angry at one person but not others for same thing could be about dislike of the person, sure, but there might be other reasons too, like if it's in the workplace, the person would be less inclined to blow their stack at the boss but at subordinates, no problem. Or if the person thinks their target won't react, then away they go. Or if the other person is bigger than them then suddenly they remain silent etc. It could be a few things...🤔