Effect on the actresses playing the daughters

First of all - Wow. This must be one of the best movies when it comes to non-stop suspense, realistic depiction of violence, straight forwardness and, for me, acting.
For the suspense, once the riot starts, there is not a single scene where you don't feel that *beep* is going to get even worst, no unnecessary family moments, long talks about something that has absolutely nothing to do with what is going on, just a family trying to survive that focuses on the task at hand.
The realistic depiction of violence can be put together with the straight forwardness. People seem to have some misconceptions as to what happens when there is a revolution - the forum is full of people saying how it doesn't make sense that they are killing their own people or that the violence is gratuitous. If you read a bit about revolutions in this part of Asia, you will find out that the producers actually show a pg-13 version. I won't describe all the atrocities committed in the name of ridding the country of an unwanted element because I'm not that good at english and because there's quite a lot to go on… The execution by truck may seem weird or over the top but that's the way they Red Khmers were doing it for real... The straight forwardness is how you don't expect a last second hero to appear out of nowhere and save the poor man about to be chopped to pieces - it just happens, the way it would in real life.
Also, I know that children actors are very protected from violence on the set but still - that last scene must have had an effect on the little girl… If I was pretty shaken up while sitting on the couch, smoking weed and eating pizza I can't imagine how she must have felt. Even if they explained everything to her, used some tricks to make here feel safe and comfortable or whatever, she is still a little girl who had to point a gun at another persons head while some dude was shouting and holding a gun to hers…