Orphan - Spoiler alert!

At least I hope it will be. I'm not going to watch the movie so can someone please put me out of my misery and let me know the twist?
David
Yahoo Answers says:

The parents had a miscarriage so they decided to adopt Esther, the orphan, she's very mature for her age. They take her home and introduce her to her new sister, Max (she's deaf), and brother Daniel (he doesn't like her). Everything seems perfect about Esther and the parents spend most of their time with her than the other kids. But at school Esther is bullied by this girl and her brother does nothing to help her. One day when they are at a playground Esther pushes the mean girl off a slide and she breaks her leg. Max sees this but doesn't say anything. The mother starts to think that something is wrong with Esther when she finds out that trouble follows her everywhere she goes, as said by the lady from the orphanage. Esther overhears the parents and the lady talking and thinks she is going to take her away so she takes max with her to the road and pushes her in front of the ladys car to make her stop. She then hits her in the head with a hammer repeatedly and hides her body under a bridge, with Max's help. Then she hides the evidence and her dress (it has blood on it) in her foster brothers treehouse. Later on, Daniel finds out about it after Max shows him pictures that Esther drew of her crimes. Esther over hears Daniels plans to go to the treehouse, and later that night she threatens him. He goes to the treehouse anyway, but Esther tries to burn it down but he survies. While that is happening the mother is trying to getting information on where Esther came from. She sees the fire and stops Esther from further hurting Daniel. They go to the hospital and once there Esther sneaks into Daniels bed and suffocates him. She then goes away like nothing happened. The doctors come and try to revive him. The mother sees Esther and slaps her in the face, but the doctors sedate her and she stays at the hospital while the father takes Max and Esther home. Esther tries to seduce the father but he resists. She goes upstairs and tears her room up. She then stabs Danial a couple times and goes after Max, but Max gets away. The mother gets a call from the institute she had called earlier to get info on Esther and the "secret" is that Esther is a 33 year old psychopath. She rushes home and calls the police and makes it to the house. She and Esther fight and end up outside in the frozen lake but she successfully kills Esther. So now it's just the mom, Max, and Daniel (who is still at the hospital).
Travis Jacobs

"You might not sound so idiotic if there were at least something excitable in my post to begin with..." --Baf
Thanks! I was wondering about that myself.
Wow that was really detailed, thanks for finding that. I thought from the movie trailers that she was a six year old or something like that, not a 33 year old psychopath.
David
You scared of little girls, DL? :D

-Fred
Pirates, vampires, zombies, ninjas, ghouls, aliens, goblins, monsters, robots, sorcerers, undead, werewolves, demons, mutated dinosaur-cyborgs and those pesky phone salesmen! The shotgun is a one-size-fits-all solution!
I think it's fairly obvious we should all be scared of little girls, at least to a certain extent.
Travis Jacobs

"You might not sound so idiotic if there were at least something excitable in my post to begin with..." --Baf
Definitely, considering that they can make up tons of stuff that isn't true that can get people in trouble.

Sorry... i am drunk right now.
Matt