About a month ago a robin flew into my back door window and fell to ground and twitched for a while. It had a trickle of blood running abit down its beak. I thought it was dead, but every thirty seconds to a minute or so it would move around. I was very very close to going out there and mercy-killing it, but I just wasn't sure. Maybe it was just concussed? Maybe it broke its neck and was paralyzed? Very sad experience. I ended up going out and giving it some water and a piece of tangerine. It turned around to face the water and then began to puff up into a little ball. I let it sit there for a while while I watched it from inside. Every ten minutes or so I would go check on Mr Robin, and he must have hopped to the water because he moved. As the day faded into night I kept watch over Mr Robin, hoping for him to leave. After about ten more minutes I looked back and he was gone. Did he fly away? Did some predator sneak up and grab him? These are things we can never know, and that is the human condition.