Actually, it is called reinforced learning.
They have drummed it into their heads from birth from the home, school to religious places, that a bad brother is far better than a good neighbour.
And there is nothing that any neighbour can say to change that aspect of their lives!
Let me paraphrase an Arab saying: “I & my brothers against our cousins, my entire kindred against our neighbours;& our kindred & the neighbours against the foreigner! ” So, don’t be shocked when other West Africans have more rights in Nigeria than non-Northerners!