The sins of the fathers pass on to the 3rd and 4th generation. A statement of fact.
A pregnant woman smokes, drinks, eats too much sugar and has diabetes. The baby suffers and has more obstacles to overcome than a healthy baby from a healthy mom.
The same is true of cultural errors. A culture that reveres astrology or some false doctrine suffers for generations.
What I’m saying is, if I were Manson’s parents, forgiveness wouldn’t be any comfort at all. Indeed it would be extremely hard to believe.