The movie that comes to mind is The Forgotten. Truly horrible, wish I could have forgotten seeing it. Julianne Moore has her share of clunkers along with the gems.
I mentioned this one earlier, but it deserves a bit more description. There are aliens, and they're really really powerful. How powerful? So powerful that you never even see them. As a rule of thumb, that's usually the sign of a sucky alien movie. But how much did the aliens suck? So much that sucking was literally their move. If you said something about the aliens, you'd hear a loud whoosh and you'd get sucked up into the sky, never to be heard from again. But there were also undercover people who knew about the aliens and undercover aliens that knew about the people who knew about the aliens, and one of the undercover aliens was supposed to take julianne moores kid and make her forget about him, but obviously a mom can't forget her kids completely, so they used some alien magic on her but she still didn't forget them so they used some alien magic on everyone around her and they all forgot her ####ty kid but she couldn't so they whooshed some people in the air and she was like what the ####, I think there's some aliens, and someone said, you might be on to someth...whoosh.. and that was the end of that and then she was all, wait, I think I have a kid. And the alien who was in charge of all the alien magic to make her forget started yelling at her I want you to forget your kid... here's some ####ty alien magic... hey, seriously, forget that kid... here, I'm going to yell at you extra hard now... and she didn't forget her kid... so he was like, hey, I'm going to make you forget your kid, I'm an alien.. wait... no... whoosh. And then she got her kid back. The end. So the moral to the story is, kids are so great that even aliens can't make you forget them. ####### a.