PLEASE HELP!!! Should I Tell My Neighbour To Go & Do DNA Test On His Kids?

I live in a house with three flats and in one flat I have this couple who are my friends, the man is fairly educated and his wife is an illiterate.

The both of them quarrel regularly and since I am not a busybody , I do not interfere , all I do is listen but something has got me worried when listening to their quarrel, the woman always use the child’s paternity to insult the man, some of the insults go like this ;

“Idiot man”
“Lazy man”
“Okobo”
“Leave my children, nor be you get them, I go carry them go meet who born them”
“Nor touch my children ooo,leave them for their papa”

Surely this insults infuriate the man and his sometimes beat his wife, I myself who is more reasonable think his three children are not really his.

The wife is a trader and comes home at irregular times which also lead to quarrels , the children also do not have some facial characteristics of the said man.

I want to advise the man to do a DNA test ( only God knows if he knows what it means), but do you guys think this man is really the father or the wife is saying these things to spite him ?

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