A zillion Branches!!!

I sit down Looking to this particular family tree hmm....Big twist if you ask me...

So i'll take this step by step for you to understand!
Ayo has like 12 wives, then he has a 'fling' with another woman we call her tomilola which results in a female child tola, tomilola has other children from her marriage, so tola has half Brothers and sisters from her mother's side and her father's side lets pause for a while(i think am getting confused myself).

So i ask myself why do this people of the old generation marry each other like there was no tommorrow? were there no moral instructions? or the men and women were just too horney not satisfied and could not get enough? really am still puzzled!!

Ok back to my complicated tree...tomilola has a sister lets call her dotun who also has kids and tola has children too which makes Dotun's children and tola's chilren second cousins...here comes the real twist... one of tola's half sister's(from her fathers side) children(a girl) and dotun's son now met(obviously they don't have the same surname or any connection at all except they have a cousin in common) confusing i know just take it one step at a time...Now my question is 'would the union of this innocent children be right?'

This twist got me thinking now do we have to ask everybody we meet 'where are you from?, tell me about your grand parents union??' to be sure you are not getting involved a relation especially if you are a descendant of 'OLOJEDE' where you dont even know everybody...So i would say be careful cos u neva can tell the next person you are trying to get invoved with might just be you Grandmother's half sister's grand child and dont forget to ask 'tell me about your family tree'!!

so i need feedback!!