I'm not sure. Wish I could give you a more solid answer than that, but I honestly don't know.
What I might think is that once you've grown up with violence and seen it an an example of how to react to certain situations, that soon becomes your "go to". But that would also be assuming that the PTSD is from that sort of violence.
I've never heard of it as a symptom of PTSD, but then again, I could be wrong.