Because the ancestral family has been simple and kind for generations, their family roots are like this, and so are their descendants. Different roots have great influence on people.
Another example is the living environment. People living around garbage incineration plants have a high probability of getting lung disease, and people living on the roadside have a high probability of losing their privacy.
In short, these are really related to geographical feng shui. The ancestors have a good foundation, and the descendants are generally good. The ancestors had a bad foundation, and many descendants were not so good.