It's important to not forget genetics in the role of this. There are genes that cause anti-social behaviour, depression, alcoholism, and so on. Such people, wh

It's important to not forget genetics in the role of this. There are genes that cause anti-social behaviour, depression, alcoholism, and so on. Such people, when untreated, are quite likely to be bad parents. Their children, will indeed show a similar pattern to the parent's, but childhood abuse/neglect would be more a symptom than an underlying cause of a terrible family history. We know that because of twin and adoption studies. In many of such scenarios, what predicted a messed-up psyche was not the family someone grew up with. Instead, it was either family they were born into (adoption), or a set of genes (different correlations for mono/di-zygotic twins).