In The Curious Case of Benjamin Button, Brad Pitt's performance as the titular Benjamin is very understated and down-to-earth, just as you'd expect Benjamin himself to be. There are a lot of little treats that reflect this approach, but that's not what this entry is about. During some of the saddest scenes of the film, such as when Queenie passes away or just after Daisy and Benjamin make love for the last time, something that both are clearly aware of, Benjamin has this little smile on his face. At first, I thought that this meant that he was being wooden, but I got to thinking about it. Then it hit me. That little smile? That's the face that Benjamin shows the world when he's crying inside. I like the movie even better since I made that realization. - Aranis.
Remember the lady who told him that it must suck to grow younger because you will see everyone you love die before you? This happens. Benjamin damn-near watches everyone he once loved and cared about's death. The Irony kicks in when Daisy has to watch him die. The woman he loved and cared about so much for so long is the last one to know him.
In the scene where Caroline begins reading Benjamin's diary he says he will write down his story while he can still remember it, the scene in and of itself seems inconsequential however near the end of the movie Benjamin has dementia. This means that in 1985, the year of the journal's introduction, that he knew what was happening to him.