Remember Me
(2010)

Tyler goes to his dad's office to meet with attorneys about causing a ruckus at his sister's school.  His dad is late getting to the office because he decides to pick up Tyler's sister and give her a ride to school.  When the sister gets to school you realize that the date is September 11, 2001.  In his dad's office Tyler realizes his dad has family photos running as a slide show screen saver, and that his dad really does love the children.  Tyler looks out the office window onto a beautiful clear sky and the camera zooms out to reveal that Tyler is standing in one of the upper floors of the World Trade Center.

As Tyler's family watches the towers attacked, and then fall, they know that Tyler is gone.  Then scenes of future years play out.  Aly patches things up with her father, and goes back to riding on the subway.  Tyler's father grows closer to the little sister.  Tyler's mother counsels families of other 9-11 victims.
 

Thanks Adajean!