Creepy theory about the ending - SPOILER
We´re talkinga bout Gaspar Noe. The guy who came up with those crazy ideas seen in "Irreversible" and others alike. Wouldn´t be surprised if his real intentions about the ending, were as follows:
What on earth happened to that BABY, and why did he start crying?
Maybe I am going too far, but I think the father raped him, even if it wasn´t his intention. Because, see, while he was in the bathtub, he was already going crazy over Elektra... thinking about bathing with her and doing whatelse would come to his mind. Then the baby walks in, and what do we see on the next scene? He is crying in his father´s arms, while Murphy is saying "Gaspar, I´m so sorry, life is not easy. Please forgive me, I am lost..."
Add that to the extra-tip theory that the mother of his kid showed up before the scene, as if she KNEW what could have happened, and -in a way- she was already fed up with him drooling all over Elektra all the time. She was fed up. So, as a way to give him a taste of his own medicine, release the little lamb to the big wolf, as payback.
Just thinking that, coming from Gaspar Noe, anything is possible.