You're very welcome, and it is totally your decision, of course -- but I've let my 9yo and 5yo see the LOTR movies, yet we still do fast-forward some scenes in 2 and 3.
This is different. There are a couple of visuals that are disturbing, but there are also some very dark plot developments that are not at all "over their heads," and that might connect hurtfully with a child.
My strongest advice to you, offered precisely for what it's worth, is that you see it first. A friend from church went with his daughter, and said he regretted it, wished he'd previewed. I've never yet regretted being cautious. It's a very righteous PG-13.
Dan
Thanks, I will probably preview it then. I just figured if he could handle LOTR which was very dark and violent then he could handle anything. lol