Bird "Offs Itself" In Our Front Yard--Kids are Stunned

WARNING: GRAPHIC PICTURE BELOW!!!
(click on it for a slightly larger view)
Recently, a cowardly neighborhood robin decided to "off itself" via some string and the young red oak tree in our front yard. I'm not sure what events led to his decision. There was no note left behind and I don't remember any of the other robins speaking (or, chirping) about how difficult his life had been. Perhaps there was a shortage of worms or maybe his house had been destroyed--I don't know. Actually, just the other day I found a robin nest in the our garage (we leave the door open too much, I guess) and threw it out into the yard. Did I have something to do with this?

Anywho, I apologize for the graphic nature of this image. We are still dealing with it in our home.

On a more serious note, I really don't know what happened here. This is a real picture that I took a few years ago. I think we had some twine caught in the tree and this poor guy got stuck in it. Anyone that knows me knows that I'm a bird watcher. The more I think about it, this looks like (brace yourself for the worst pun ever) FOWL PLAY!