This was a wonderfully creative and imaginative film. I thought that it was extremely well done. However, the film makers could have toned down the violence quite a bit and still made their point that the stepfather was evil.
Parents, if you value your children's innocence and don't want them to have nightmares for weeks, do NOT let them see this movie. And I'm not just talking about little kids, I believe older children and tweens who are not already desensitized could be traumatized by some of the images. The sociopathic stepfather violently kills and tortures others with no remorse and the fantasy monsters are frightening (the "pale man" in particular).
For parents who have had been through difficult pregnancies and/or lost a baby, keep in mind that there are scenes where the mother and her unborn baby are in peril (showing blood). My wife had to stop watching about two thirds of the way through.
Even through all of that, I still thought it was an overall great story and an extremely well done and engaging film. Unfortunately, it should only be viewed by adults and teenagers who are not bothered by violence and gore. Hence the "R" rating.
What other families should know
Too much violence
Too much swearing
Too much drinking/drugs/smoking