That was not my experience with my two brothers close in age (one twin, one two years older). We never hit or fought each other. Now, we did have a younger brother with anger issues who frequently attacked us. The attacking isn’t my evidence of anger issues, just a symptom. He didn’t attack people at school, so I guess that’s evidence other people, even without anger issues, might hit siblings but not non-siblings.
That was not my experience with my two brothers close in age (one twin, one two years older). We never hit or fought each other. Now, we did have a younger brother with anger issues who frequently attacked us. The attacking isn’t my evidence of anger issues, just a symptom. He didn’t attack people at school, so I guess that’s evidence other people, even without anger issues, might hit siblings but not non-siblings.