You know what I hate? I go to the movies to watch a movie. I find a seat where I can see and hear it properly. I settle down to watch. Then a fat guy invariably comes and sits in front of me at the last minute... I hate it!
Madness string 693
Kids have a fundamental sense of fairness and when they see a situation where they feel things are unfair, they will sacrifice their own advantage or sacrifice to punish those behaving selfishly in order to maintain fairness. I imagine that you noticed the injustice in the inequality of how your parents treated you both as a child and used your kid logic to correct that injustice to maintain fairness.