lovecraft68
Bad Doggie
- Joined
- Jul 13, 2009
- Posts
- 42,028
I thought the idea was that the aversion to sex between siblings originated from the experience of watching your common parent (mother, normally) raise your sibling. If you weren't raised with your sibling then the effect didn't exist.
That could be part of it, the theory conveniently covers a lot of things
But you keyed on something and that is watching a parent. My take is in real life cases of consensual incest between sibs, something is seriously wrong in the home. Something is missing, something is fucked up to cause the sibs to become close in that way.